1 

# Manganese

From Wood-Fired Boilers

Dan Ahern PE

March 20042 

### Acknowledgments

This document was prepared under EPA’s Office of Research and Development’s (ORD) program called the Regi onal Research Partnership Program (RRPP). This program provides short-term training opportunities for EPA Regi onal Office Staff to work directly with ORD scientists at ORD laboratories.

The primary scientists assisting on the proj ect were David Tingey and Bill Hogsett of

ORD’s National Health & Environmental Effects Research Laboratory (NHEERL), Western Ecology Division in Corvallis Oregon. They were the mentors for this study and provided direction and assistance durin g the study. The Western Ecology Laboratory provided workspace and logistic support during the in itial development of the project activities.

There were a number of other scientists at ORD labs that provided assistance in this study. They included:

Ken Hudnell of NHEERL in Research Tri angle Park (RTP) on medical effects of

manganese. Joe Behar of National Exposure Research Laboratory (NERL) in Las Vegas on manganese mobile source issues. John Kinsey, Dean Smith and Michael Ha yes of the National Risk Management Research Laboratory (NRMRL) at RTP on wood stove and prescribed burning issues.

There were an number of other parties that provided data and insight during this review and they are listed in the contact list in attached contact list.

The Air, Pesticides and Toxic Management Div ision Director, Beverly Banister, provided the time and support in the Atlanta Regi onal Office to complete this study.3 

## Contents

1. 

### Executive Summary 4

2. Background 5

3. Manganese Sources and Effects 6

4. Medical Effects of Manganese 7

5. Manganese and Plants 12

6. Emissions of Manganese from Burning 19

7. Manganese Emissions and Air Quality 22

8. Summary and Conclusions 25

Appendix 1 - References 27

Appendix 2 - Contacts 3145 

### Executive Summary Manganese and Wood-Fired Boilers

Manganese is widely distributed in earth’s rocks and soil. It is the twelve most abundant element. Consumption of Manganes e is primarily (90+ %) a ttributed to steelmaking and other metallurgical uses, with other uses bei ng in dry cell batteries, animal feed, plant fertilizer, and water treatment chemicals.

High levels of Manganese exposure leads to a neurologic disease called manganism. Manganism symptoms include dull affect, al tered gait, fine tremor and sometimes psychiatric disturbances. Concern for Mn ex posure seems less than its low inhalation Minimum Risk Level (MRL) would call for. Studies on Mn have been mainly in the occupational area and due to the lack of dat a on effects to potentially susceptible populations, there is a high safe ty factor built into the dev elopment of the MRL. It certainly seems that further medical research is needed to determine if this low MRL is justified and determine a MRL with a reasonable safety factor.

Manganese has been linked to violent behavior in young adults and learning impacts on children. Occupational and follow-up studies show that Mn exposure effects are permanent and progress even after exposure has ceased. While the long-term effect of exposure is the development of manganis m, which is a disabling syndrome of neurological effects, many relatively mild symptoms occur early on in the exposure.

It appears that Mn is the primary HAP metal in wood/bark used in wood-fired boilers. Levels in bark appear higher than in trunk wood and Mn levels in leaves can vary by orders of magnitude with levels running from 1 to over 1 000 ppm. Existing data does not reveal this range in wood and bark, used in boilers, where the range of levels ran from 4 to 184 mg/kg. Current data is not sufficient to say that certain species or geographic areas will have different levels of Mn in their wood/bark. This would be a good area for future study since the limited data indicates possi ble differences.

Mn is by far the HAP metal emitted in the greatest amount, from wood-fired boilers. It

accounts for over 90% of the HAP metal emissions from burning wood. Most woodfired boilers will be covered by an upcoming MACT standard and will be required to provide particulate control. This will also reduce Mn emissions. The controls will reduce Mn emissions to levels experienced in w ood-stoves and fireplaces. There is need to

determine emission factors for Mn fr om wild fires and prescribed burns.

There is not a good correlation between ambient air concentrations of Mn and reported TRI releases. There appears to be a lack or coordination between reported emission inventory data and what is being reported in TRI reports. Mini-steel mills and metal

foundries need further investi gation to better estimate em issions of Mn from their operations.67 

## Background

The reason for this study was work per formed by the EPA Region 4 Toxic Release Inventory (TRI) Staff on a new modeling program from EPA’s Office of Pollution

Prevention and Toxics calle d the Risk-Screening Environmental Indicators (RSEI). This model supplements a quantity-based view of the TRI releases by incorporating toxicity information and exposure models that assess, at a screening-level, the relative-risk that chemicals released may pose. This unpublished report entitled “US EPA Region 4 Relative Risk Initiative, 1999 TRI Air Rele ase Data” (1) reported that Manganese (Mn) compounds was the number one chemical when ranked by the RSEI relative-riskrelated value. It ranked in t he top five chemicals in seven of the eight Region 4 states.

This new data from our TRI staff wa s of great interest because Manganese and Manganese Compounds were not part of any ongoi ng P2 activities. Further work with

the TRI staff on industrial se ctors contributing to Manganese releases, indicated that a

number of sources were from wood-fir ed boilers. Wood-fired boilers are used extensively in Lumber (SIC 24) , Furniture (SIC 25) and Paper (SIC 26) sectors. Region 4 averages (1999-2001) about 45 of the top 100 TRI reporting faci lities in these sectors reporting Manganese and Manganese Compound releases.

One significant annual increas e in reported Mn emissions ca me from a facility that had a wood-fired boiler. Upon inve stigation, the facility report ed raising its emission factors based on input from a sector technical support group. (2)

This combination of a newly-identified chemic al risk, the large number of these sources in Region 4, and possible understating of em ission factors from wood-fired boilers, leads to a need for better understanding of t he risk and the actions that could be taken

to reduce this risk.

Very little information could be found initia lly on Manganese emissions from wood-fired boilers and the region could not idenify progr ams already looking into issues with Mn. To dedicate some time to this regional c oncern, a proposal was submitted under the Regional Research Partnership Program (RR PP) to study Manganese levels in wood

fuels obtained from various forest types and determine if they vary with geography and or soil types.

EPA’s Office of Research and Development (ORD) accepted this proposal and ORD’s Western Ecology Lab in Corvallis, Oregon agreed to support this study.8 

## Manganese

Sources and Effects

Manganese was first recognized as an element and isolated in 1774. It is a metal that from a chemical standpoint is related closely to iron. Fr om a metallurgical standpoint, manganese differs from iron (and it s other atomic neighbors - coba lt and nickel) in that it does not possess useful physical properties as relatively pure metal. Its principle industrial application is to serve as an alloying element.

Manganese is widely distributed in the earth’s igneous, sedimentary, and metamorphic

rocks. It has been calculated to be the tw elfth most abundant element on the earth’s crust. Only aluminum, iron, magnesium, and titanium metals are more abundant than manganese.(3)

Manganese has been used in making steel sinc e 1839, but did not come into general use until the later part of the 19 th century with great er use of the Bessemer Process. The domestic consumption of manganese is primarily (90+%) attributable to steelmaking and other metallurgical uses. M anganese is also used in dry cell batteries, animal feed, plant fertilizer and water treatment chemicals.(4)

About 700,000 metric tons of Manganese was us ed in 2001. (5) None of this metal is mined in the US. Only one plant in this country processes manganese into ferromanganese ores to be used in steel making, all other processed ores are imported.

The first report of human illness due to manganese was identified in 1837 and later

rediscovered in the twentieth c entury. Manganese is an ess ential nutrient for plants and animals, but at higher exposure levels is a neurotoxin in humans. The most critical exposure is from inhalation that seems to bypass the human ingestion barriers to impact the central nervous system.(6)

Manganese material flow pattern work by the Department of Interior (4) estimates that air emissions of manganese has increased 45% due to human activities. They list the following anthropogenic sources as energy production (coal and oil combustion); mining; smelting and refining; steel and ir on manufacturing; and wa ste incineration.

Most material flow work does not consider manganese emi ssions from anthropogenic wood burning, even though the D epartment of Interior es timate that the manganese

emissions from forest fires is greater than the world-wide emissions from steel and iron manufacturing.9 Manganese is identified as a priority candidate chemical by Centers for Disease Control and Prevention, for inclusion in the National Report on Human Exposure to Environmental Chemicals.(7)



## Medical Effects of Manganese

Manganese (Mn) is considered an essentia l element both for humans and plants. Humans are exposed to Mn in food and water they eat and drink and in the air they

breathe. It is considered an esse ntial nutrient because of its involvement in many of the body’s enzymatic reactions. (6) Diets with too li ttle Mn can lead to slowed blood clotting, skin problems, changes in hair color, lowered cholesterol le vels and other alterations in metabolism (8). There is a lack of consensus about the recommended daily allowances, but normal diets seem to pr ovide the necessary levels of Mn. (3)

There seems to be a narrow line between the recommended Mn requirements (2-5 mg/day) and the oral Reference Dose (RfD), which is ~ 10 mg/day for a 70 kg person.(6) It seems that the body processes the dietary Mn that it needs and the excess

is excreted in the feces. Inhaled Mn be haves differently, it bypasses the body’s liver

and blood-brain barrier and accesses the C entral Nervous System (CNS) directly.

High exposure to Mn, via inha lation, causes a neurologic disease called manganism. First noted in manganese miners, this dis ease has a combination of symptoms that

include mental and emoti onal disturbances and slow and clumsy body movements. Although similar to Parkinson symptoms, it is a different disease. These effects are caused by brain damage and the br ain injury is permanent (8). A number of effects that

have been identified in occupational workers that are less severe and have been related to exposure to lower levels of Mn. There are a number of epidemi ological studies of workers exposed to Mn below the American Conference of Governmental Industrial Hygenists Threshold Limit Value that hav e shown neurobehavioral, reproductive and respiratory effects(9). The inha lation RfD was established bas ed on the work of Roels et al in 1992 (10) on the detect ed preclinical neurological effe cts. These effects included visual reaction time, eye-hand coordination and hand steadiness.

There appears to be no evidence to determine whether or not Mn is carcinogenic and some reports that suggest that it may even be protective agai nst cancer (9). Therefore EPA considers Mn to have only potentia l for chronic noncancer effects.

The inhalation Reference Dose (RfC) and the Minimal Risk Level (MRL) developed by the Agency for Toxic Substances and Diseas e Registry (ATSDR) of CDC for Mn is lower than some of the other perceived high risk metals. Table 1 below compares the10 inhalation MRL and Reference Doses (RfD) for selected metals based on ATSDR’s toxicological profiles for these substances http://atsdr1.cdc.gov/toxpro2.htm It is surprising that the RfD for Mn is six times mo re stringent than that for Mercury. This

does not match what the States have est ablished as acceptable ambient concentrations in their air regulations and guidelines. In fact, in one Region 4 state, the acceptable ambient Mn level was 25 ug/m3 and the mercury level was 0.25 ug/m3. The level of 25 ug/m3 for Mn is 500 times the RfD of 0.05 ug/m3! The merc ury level of 0.25 ug/m3 is

below the RfD of 0.3 and above AT SDR MRL level of 0.2 ug/m3.

The low values for Mn are in great part due to the high level of uncertainty in taking the Lowest Observed Adverse Effect Level (LOAEL ) or No-Observed Adverse Effect Level (NOAEL) to the reference dose or minimal risk level. Table 1 indicates that the safety factor for Mn is nearly an order of magnitude hi gher than the other metals and this

reflects a number of unknowns about Mn. This higher factor reflec ts the lack of studies on Mn for groups other than in occupational st udies and other uncertainties with existing

data. This low inhalation value for Mn has no t filtered down to Stat e Acceptable Ambient

Air levels or other reduction initiati ves that exist for mercury and lead.

Table 1 Comparison of Inhalation MRL and RfD for Selected Metals

Uncertainty

Metal MRL RfD Factor State Acceptable Ambient Range ug/m3 ug/m3 ug/m3 Manganese 0.04 0.05 2100 0.24 to 119 Mercury 0.2 0.3 125 0.01 to 0.75

Lead* 0.14 210 0.09 to 1.5

Chromium IV 0.005 0.008 400 0.0001 to 0.3

* MRL not derived by ASTDR. EPA did not gener ate an RfD that it feels inappropriate because some health effects associated with exposure to lead occur at blood levels as low as to be essentially without threshold.

OSHA established action level of 30 ug/m3 for workplace exposure. The imputed MRL for lead was developed by applying the manganese uncertainty factors except for “an uncertainty factor of

10 to account for limitations in the inhalation database, including the lack of data on developmental e ffects and data on the potential for reproductive effects in women, and potential for differences in toxicity from different forms of manganese”.

As mentioned above, inhaled Mn bypasses the liver and blood-brain barrier that ingested Mn is subject to and accesses the CNS directly. Originally only the fine Mn fraction was thought to pose substantial hu man-health risk due to its ability to reach11 deep in the lung, but some researchers hav e discovered another access to the CNS via coarse fraction Mn deposited in the nasal mucosa.(11)

The medical impact of Mn seems to correlate with some effects of lead. There seems to be three separate impacts from excessive Mn exposure and they relate to children, young adults and long term occupational or area exposure.

Effect of Mn exposure on Children Most manganese studies have been in occupati onal studies. Some limited studies on children show increased respiratory compla ints and learning problems. A study in

China indicated lower mental performance in students exposed to higher levels of manganese. Investigations showed that students who performed poorer in school had higher manganese hair

content than children in a contro l group (8). These studies ar e not sufficient to establish cause-effect relationship since a number of other agents, including lead might also be

involved. Other studies indicate that infant s and children may be more susceptible to Mn exposure because they retain a much higher percentage of i ngested or injected Mn than adults. Formulas for infants contain higher le vels of Mn than breast milk, but apparently no studies suggest whether this is unhealthy or not.

Effect of Mn exposure on young adults

A number of researchers have hypothesized that violent behavior is associated with excessive body burdens of Mn and other metals like lead and cadmium. The hypothesis holds that a cert ain percentage of the populatio n can not properly handle the environmental loading of metals and this gr oup accumulates higher levels of heavy metals. These higher levels lead to vi olent behavior. One researcher (Needleman) estimates that 11 to 38 percent of all violent crime can be traced back to these metals.(12) Another researcher measured si gnificantly higher Mn levels in several groups of prisoners held for violent crimes than nonviolent prisoner s and other control populations (6). Master et al (13) compared the Toxic Re lease Inventory (TRI) release figures and the Federal Bureau of Investigat ion (FBI) violent crime database. After controlling for many socioeconomic and demogr aphic variables they showed significant positive associations between releases of Mn and lead and increased violent crime rates. Masters also reported that dietary deficit s of calcium and zinc and other essential vitamins can lead to greater adsorption of Mn and lead. It would be very interesting to see research on using these supplements to s ee if this would reverse the Mn and lead levels and possibly show changes in behavior of violent criminals. Masters also reported that Lithium has been found to detoxify manganese.

This hypothesis has considerable import for work ongoing that is studying the potential effects of a gasoline additive called Methylcyclopentadienyl Manganese Tricabonyl (MMT). This additive, which is prohibited in t he US, is used in Canada. Masters reports

that the since the introduction of MMT in Canada, the rate of all violent crimes has12 increased at a faster rate in Canada than in the US. US EPA Office of Research and Development is conducting another reevalua tion of the risks of MMT that will update their 1994 study (9). This study should be released in 2004.

It is difficult to separate the impacts of Mn and Lead. Masters included both, in his work. Another researcher Nevin (12) r eported a strong associ ation with a drop of murders committed by children under the age of 18 with the exposure reduction of lead with a lag of 23 years. It is c ause of concern for these resear chers that Mn could step in the void left from the elimination of lead in gasoline.

Unfortunately Masters did his work utiliz ing TRI data and missed the highest ambient Mn level recorded in the US. This town, East Liverpool, Ohio, did not have Mn releases reported in TRI. As will be discussed later, there are some unexplained gaps in TRI emission figures and measured ambient air leve ls. Table 2 compares three towns in

Ohio that had ambient ai r monitoring stations.

East Liverpool, Ohio has the dubious distinct ion of having the highest recorded ambient level of Mn in the nation. Unfortunately, TRI data showed few reported releases. This town had no reported releases from facilitie s in town and only about 600 lbs from the surrounding county. Another town, Marietta Ohio also has a dubious distinction of having the only remaining Ferro-manganese a lloy plant and has the highest reported

TRI air releases of Mn in t he country. This plant reported releasing 431,000 lbs of Mn in

2000.

Table 2 does not indicate a good correlation between ambient Mn levels and FBI violent

crime statistics. All three towns have low crime rates and the rate per thousand people in E. Liverpool is not significantly higher (1.7 vs 1.3) than Bellefo ntaine, which had low

ambient Mn level.

Additional work was done with South Carolina statistics. This state has one of the better ambient air monitoring networks. Li mited review seemed to indicate some correlation but it was hampered by lack of FBI st atistics in that st ate (The city with the highest ambient Mn levels had no statistics in the FBI database). Ken Hudnell at ORD NHEERL has done some additional work in this area and by including other crime

statistics like domestic violence and other as sault figures, did get a better association comparing Marietta with Athens, Ohio.

Table 2 Ambient Manganese level a nd FBI Violent Crime Rates

2000 Ambient Air Data and FBI statistics

Item/City Bellefontaine Ma rietta E. Liverpool

Population 13,092 14, 541 13,11313 Median Income $36,029 $29,863 $23,138 Ethnic Diversity 92.4%Cau 98.2%Cau. 94% Cau.

Murder 0 0 0 Rape 10 9 6 Robbery 4 4 11 Aggr Assualt 3 8 5

TSP Mn Levels ND* 0.4ug/m3*** 0.7-1.5ug/m3** (Annual Average) * no detect (below 0.1ug/m3) at monitoring station (11 samples) ** Two monitoring sites

*** State site data not on national air quality system

Effects of Long term Mn Exposure

Again most of the research and studies have been occupational but it appears that damage is permanent and therefor e may be cumulative. ATSDR list those over 50 as a more susceptible population to the adv erse effects of m anganese exposure. The Toxicological Profile for Manganese list numerous studies on the effects of Mn(8) Some follow-up studies suggest that there is cont inuing deterioration of health after exposure had ceased. Huang et al (14) reported that workers in a ferroalloy plant that were chronically exposed to Mn continued to s how progression of clinical symptoms of manganism, 9 to 10 years after exposure had ceased. Their levels of manganese in blood, urine, scalp and hair revealed a dras tic drop in manganese concentrations but

their health continued to decline. Some ot her studies report that impaired sexual function may in men may be the earliest clinic al manifestations of manganism. Many studies indicate impotence and lack of sexual desire were higher in groups exposed to

Mn.

There does not seem to be many long term follow-up studies for effects of Mn exposure. The aging process may mask the sub clinical effects of manganism. The similarity between some symptoms of manganism and Parkinson dis eases may lead to confusion

and better differentiation between the two may be needed. Despite the similarities, significant differences exist between the two. Hopefully future epidimiologic studies will14 determine rates in older populations so that appropriate attention and identification can be given to long term exposure.

Summary

High levels of Manganese exposure leads to a neurologic disease called manganism. Manganism symptoms include dull affect, al tered gait, fine tremor and sometimes psychiatric disturbances. Concern for Mn ex posure seems less than its low inhalation RfC and Minimum Risk Level (MRL) would call fo r. Studies on Mn have been mainly in the occupational area and due to the lack of data on effects to potentially susceptible populations, there is a high safe ty factor built into the dev elopment of the MRL. It certainly seems that further medical research is needed to determine if this low MRL is justified and determine a MRL with a reasonable safety factor.

Manganese has been linked to violent behavior in young adults and learning impacts on children. Occupational and follow-up studies show that Mn exposure effects are permanent and progress even after exposure has ceased. While the long-term effect of exposure is the development of manganis m, which is a disabling syndrome of neurological effects, many relatively mild symptoms occur early on in the exposure.



## Manganese and Plants

One of the initial investigat ive questions in this review was “How much Mn Comes into

the Wood-fired Boiler”. The reviews in this area tried to determine if the Mn levels in wood was different for different spec ies and for different soil conditions.

Manganese is widely distributed in the earth’s rocks and has been calculated to be the

twelfth most abundant element in the earth’s crust. (3) The average concentration of manganese in soil from one reference is 800 ppm. The US Geological Survey collected soil samples in 1961 from 863 sites in the continental US and t he amount of manganese varied from 2 to 7000 ppm with an arit hmetic mean of 560 ppm. Manganese is considered a micronutrient (essential but needed only in small amounts) for plants and has functions in many plant processes.(15)

The availability of Mn to pl ants is affected by numerous soil characteristics like total or easily reducible manganese; pH; concentrati ons of other cations; organic-matter15 content; drainage; compaction; temperature; and microbial activity, of these the pH seems to be a primary factor. Plants absor b manganese primarily in the divalent state and lowering the pH favors the reducti on of manganese to this form and thereby increasing its solubility and availability. Sm all changes in these soil characteristics can

determine whether the available Mn will be def icient, adequate or toxic for a given crop. Once taken up and incorporated into plant ti ssue, manganese is relatively immobile in the plant. (16)

There is considerable data on Mn levels in food. This data indi cates that different species of plants concentrate Mn at different levels varying from Apricots at 0.2 ug/g to tea at 275.6 ug/g. Mo re data on levels in food are shown in Table 3.(3)

Table 3 Manganese in Food

Item Manganese Conc. Range High Low ug/g

Grains and Cereals 1.42- 17.8 Barley Rice Fruit 0.20- 4.68 Raisins Apricot

Nuts 0.38- 35.1 Pecans Coconut Vegetables 0.24- 12.7 Peas Green beans

Misc. 0.95- 275.6 Tea Garlic

The question now becomes does Mn levels vary between species of trees with the same soil characteristics, since it will va ry between different species of plants.

Considerable research has been conducted on the right balance of pH and available Mn on trees to prevent deficiency or toxicity. Unfortunately most research on trees studied the deficiency or toxicity based on Mn in

leaf samples. Very little data were found to rela te levels in tree leaves to levels in the wood or bark. Data on testing indicates that trees exhibit a deficiency of Mn when their leaf/needle levels get below 20 ppm. A dequate range is around 30 to 300 ppm range. Tree toxicity is indicated with leaf values ov er 400. Some testing showed levels as high as 2000 ppm in trees suffering toxic levels of Mn. A sample of test result s from various sources is presented in table 4.

Table 4 Deficient, Adequate and Toxic Ma nganese Concentration in Plants Leave samples in ppm (dry wt)16 Data from Reference (P) unless noted

Tree Deficient Adequate Toxic

Almond 5-25 96 ---- Apple 15 30 400 Apple(17)(18) 25-100 540-865 Orange 15-19 20-200 100-1000

Pecan ------ 141-196 ------ Avocado(19) 232-950 2000 Frazer Fir(20) 11 30-300 Black Walnut(21) 25 46-500 750 Silver Fir(22) (ug/g) 1.5-3.7 30-526

The big question is; Are these varying levels in leaves reflective of the levels in wood and bark? Unfortunately this can not be answered. While much work was done on leave/needle concentration, only one source was found that measured both needle and woody shoots(22). This work in Switze rland did detailed work on both healthy and Mndeficient trees. This research clearly show s the impact of pH on Mn levels in needles and woody shoots. There is near ly a two order magnitude difference in Mn levels from deficient trees in high pH areas and those with lower pH area. Since this work was all on one species of tree it is a good indicator t hat Mn level in needles/shoots in similar trees can vary based on soil conditions. This research also shows that there is some

modification in Mn between needles and shoots. Shoots tend to have lower Mn levels than high Mn needles and higher Mn levels than deficient tree needles. Studies were

not found that looked into whether this modi fication is carried on further in the trunk

wood and bark. Lower levels in bark and wood samples indicate th is might be taking place. The data from the Switzerl and study is presented in Table 5

Table 5

Mn Concentration in Needle and Shoots of Silver Fir Trees Mean values in ug/g

Year Plant Part Heal thy Trees Mn-Deficient Trees Group A Group B Group C Group D

1992 Needles 30.29 2.35 1.5

1992 Shoots 18.47 3.47 4.3817 1994 Needles 526 46.8 3.76 1.82

1994 Shoots 478 23.3 2.81 3.02

1994 Soil pH 3.7-4.4 5. 8-6.5 7.0-7.1 7.0-7.1

While there were no studies found that measur ed modification of Mn levels from leaves to trunk wood and bark, data on bark and wood Mn levels do not show the high variation

found in leaves and needles. Bark and wood dat a by the National Council for Air and Stream Improvement (NCASI) that supports the paper industry shows a much lower range of variation than the l eaf data. No data was found that came close to the 478 ug/g values in healthy shoots in the Silver Fir Study.

The NCASI and American Furnit ure Manufacturer’s Associat ion (AFMA) (23) data are presented in Tables 6 and 7 below. The NC ASI data indicates that Bark samples generally contain higher levels of Mn than th e wood chips. Unfortunately there was not enough data to make conclusions on the geogr aphic location or the type of tree the samples came from. The limited data does indicate that the Southeast samples are higher and that Aspen and Fir samples show the lowest levels on Mn. While these data

were not sufficient to draw conclusions abo ut Mn levels being impacted by geographic area, a study on another boiler fuel gives str ong evidence of variation. The Sugarcane Industry uses cane waste called Bagasse in t heir boilers. While not a tree fuel, it has

similar heat content and is burned in similar boilers as the wood fired ones. A study on stack test results (24) repor ted that average Mn content of Bagasse in three Louisiana Mills (32.4 ppm) to be nearly three times as high as three Florida Mills (11.7 ppm)

Table 6 NCASI Manganese Data

Geographic Area Manganese Levels in mg/kg (number of samples) Ave. Min. Max

Wood Northeast (1) 39.0 39.0 39.0 Southeast (8) 47.5 14.0 78.0 Midwest (7) 19.5 4.3 33.318 Northwest (8) 17.4 7.3 38.7

Bark * Northeast (0) Southeast (1) 165.0 165.0 165.0 Midwest (2) 90.8 75.7 106.0 Northwest (6) 94.2 21.5 184.0

* There may be opportunities to increase knowle dge on Mn levels for bark. During this study, it was learned that NCASI was work ing with American Forest and Paper Product Industry to analyze about 300 bark samples collected from member firms from around the country. This was being done as part of a response to t he proposed Industrial Boiler MACT. While presently they only pl an to measure mercury and chloride in the samples, the availability of these sample s offers an opportunity to increase the data base and observe species and geographic differences.

The AFMA recently collected samples (22) because they felt that the wood being

burned in their members boilers would have lowe r levels of metals than the mixed and dirty wood burned in Pulp Mill bo ilers. Most of the wood burned in their member firms was either sawdust or chips from the furnit ure manufacturing proce ss. Most of their

member firms had mechanical controls as opposed to the pulp mills who generally had

ESP or wet scrubbers. The data showed similar results as the NCASI Southeast wood data.(AFMA aver - 46.2 and NCASI aver - 47.5). Most of the AFMA wood measured was from areas around the plant s in NC and VA, with some fr om TN and PA, so it would be representative of Southeast. Th is similarity in values also seems to indicate that there would not be a significant difference in southeast species since the AFMA results are mostly hardwoods and the NCASI resu lts are most likely from softwoods.

Table 7

Data From American Furniture Manufacturer's Association (AFMA) October 14, 2003 report

Facility Type of wood Wood Wood Bottom Ash Fly Ash (location*) (wood chips) lb/MMBtu mg/kg mg/kg mg/kg A Poplar & Ash 0. 0046 39.6 9720 711019 A Poplar & Ash 28.4

B 0.0038 29 8260 6620

B 26.7 C Mixed 0.0086 61.7 15,400
14,400

C Mixed 64.9 D dry mix 0.006 40.6 6450 10100 D dry mix 48.1 E hard various spec 0.0052 40.9 852 5680 E hard various spec 36.2

F Hard/soft 90/10 0.0067 48.8 6960 8180

F Hard/soft 90/10 49.7 G MixSolid & Plywood 50 /50 0.01 69.2 10400 17400 G MixSolid & Plywood 50/50 78.6 H** Poplar/Oak/composit e 60/30/10 0.0034 27.2 5630 5850 H** Poplar/Oak/com posite 60/30/10 23.2 I Poplar/Cherry/Lenga 50/ 25/25 0.0076 57.8 6690 8150 I Poplar/Cherry/Lenga 50/25/25 54.3 J Chips/hoggedwood/dust 80/10/10 0.002 29.9 5850

* Facilities located in NC and VA bu t wood from PA, NC, TN and VA ** wood dust not chips

The data above shows that levels of Mn in wood and bark may vary by species and geographic area. Is this level significant and are there other metals that may be more significant? Mn is not the only metal in wood products but of the Hazardous Air Pollutant (HAP) metals, it is by far the most comm on in wood. The data in table 8 from NCASI analysis of wood samples shows that Mn is at least an order of magnitude higher than any of the other nine HAP metals . With the exception on mercury that will be released as a vapor, no other HAP metals are of significance. The section on burning will discuss whether Mn levels are significant.

Table 8

Hazardous Air Pollutant Metals in Wood Samples

Metal Number of Samples Average mg/kg Percent Detects*20 Arsenic 25 0.23 23 Beryllium 17 0.01 0

Cadmium 23 0.11 31

Chromium 26 0.22 24

Cobalt 20 0.02 0

Lead 22 0.58 25 Manganese 34 33.6 100 Mercury 23 0.86 87.5

Nickel 22 1.06 45.5

Selenium 15 0.71 33

* values below quantification level added to average when analysis does not detect

measurable levels

Summary

It appears that Mn is the primary HAP metal in wood/bark used in wood-fired boilers. Levels in bark appear higher than in trunk wood and Mn levels in leaves can vary by orders of magnitude with levels running from 1 to over 1 000 ppm. Existing data does not reveal this range in wood and bark, used in boilers, where the range of levels ran from 4 to 184 mg/kg. Curr ent data are not sufficient to say that certain species or geographic areas will have different levels of Mn in their wood/bark. This would be a good area for future study since the limited data indicates possi ble differences.21 

## Emissions of Manganese from Burning

Another investigative question in this revi ew was to find out “what happens in the woodfired boiler?”. After looking at this ques tion the investigation was carried further to determine, what happens in wood stoves /fireplaces and in prescribed burns and

wildfires.

Mn melts at 1245 C and boils at 1962 C. It has higher values than lead and lower than iron. Most boilers operate below 1000 C an d the highest temper atures are around 1400

C. Therefore emissions of Mn from boilers are as solid particulates.

EPA’s Compilation of Air Pollution Emission Fa ctors AP-42 (Chapter 1.6) has factors for

Mn from Wood Residue Combustion in Boilers. These factors for HAP metals mirror the levels found in wood and Mn again constitutes over 90 % of the tota l emissions of these metals. The factors are given in table 9.(26) and indicate that Mn is by far the biggest

contribution to Metal HAP emission.

Table 9



### HAP Metals Emission Factors

From Wood Residual Combustion

In Boilers

Metal HAP AP-42 Emission Factor

, Fifth Edition (lb/MMBtu)

Arsenic 2.2E-05 Beryllium 1.1E-06

Cadmium 4.1E-05

Chromium 2.1E-05

Cobalt 6.5E-06

Lead 4.8E-05 Manganese 1.6E-03 Mercury 3.5E-06

Nickel 3.3E-05

Selenium 2.8E-06

Total 1.7E-03

The Emission Factor for Mn was increased in t he Fifth Edition of AP 42 to 1.6E-03 from an old 2/99 factor of 9.79E-04, by utilizing about 24 reported stack tests that showed a range from 9.66E-11 to 9.77E- 03. (27) Data having 7 or ders of magnitude range is unusual. It appears that emission measur ements with and without controls were22 included in the results. A recent stack test by the AFMA in August 2003 indicates a Mn

emission rate of 3.82E-03 lb/MMBtu. This st ack test also did a fuel analysis on this tested boiler and the average Mn c ontent was 5.9E-03 lb/MMBtu. This indicates that nearly 2/3rds of the Mn in t he wood goes up the stack. Most ash tests indicate more Mn in the Fly ash than the bottom ash (see tabl e 7). One study in Canada indicated 90 percent of the Mn was in the Fly ash. (37) The AFMA test (though not stated) must have been before particulate control from the boile r’s dust collector that was estimated to have an efficiency of approximately 50 percent.

The four most common control devices used to reduce PM emissions from wood-fired

boilers are mechanical collect ors, wet scrubbers, electrosta tic precipitators (ESPs) and

fabric filters. The removal efficiencies of these control devices range from a low value

of 35% for certain mechanical devices to 99 % for ESPs. Further evidence that the AP42 value included data from controlled emissi on tests is shown by comparing NCASI data from their technical bulletin (TB). Their mean value with me chanical control is higher(3.2E-03) than the AP 42 value of 1.6E-03. Table 10 shows the expected emissions utilizing controls. One to two order of magnitude reductions in expected

emissions can be obtained with controls.



### Table 10 Control Removal Efficiency and E stimated Emission Factors for Mn

Control Device Removal Effici ency Revised Emission Factor NCASI

Values %(GG) Lb/MMBtu TB858(mean)

Mechanical Collectors 25-65 1.2E-03 - 0.56E-03 3.2E-03

Wet Scubbers 85+ 2.4E-04 4.0E-05

ESPs 90-99 1.6E-04- 1.6E-05 1.5E-04*

Fabric Filters 80+ 3.2E-04 ND

* Later work with an individual Pulp mill pe rmitee indicated their emission factor to be 3.25E-05 after ESP control, based on a stack test at similar boiler at another on of their company’s plant.

Review of boilers by sectors indicates that most wood-fired boilers in the Pulp sector (SIC 26) have ESP controls. Many of the pulp mill boilers had high stacks (most over 100 feet with some up to 250 ft high). Most boilers in the Furniture sector (SIC -25)

have mechanical collectors. It was also reported (28) t hat the percentage of wood residue that was burned rather

than sold increased betw een 1992-1997 in West Virginia. It is not known if this is a widespread or c ontinuing trend.23 The secondary question came up on what happens in wood furnaces and fireplaces that do not have the particulate control devices t hat boilers have. The impact Wildfires and prescribed burning on Mn emissions was also of some concern because of the Department of Interior’s Mn ma terial flow from wild forest fires. This document (4)

estimates worldwide emissions of Mn from forest fires as 23 thousand metric tons and the anthropogenic sources as 38 thousand metric tons. This repo rt did not include

wood-fired boilers and residential w oodburning as an anthropogenic source.

AP 42 has sections for Wildfires and Pre scribed burns (Ch 13.1), Residential Wood Stove (Ch 1.10) and Residential Fireplaces (C h 1.9). The only Mn emission factor given

for these three sources is for Wood Stoves . These were given in lb/ton of wood and

can be converted to lb/MMBtu with the conver sion factor from the residential fireplace chapter of 17.3 MMBtu/ton. Utilizing this conversion gi ves emission factors ranging

from 0.8E-05 lb/MMBtu to 1. 2E-05 lb/MMBtu. This emissi on factor is two orders of magnitude less that for wood-fired boilers a nd is less than these boilers with the best

controls. Wood stoves have more emissi on of particulates(PM10) than boilers and AP42 gives stove ranges from 0.84 to 1.77 lb/MMBtu, while the boiler range is given as

0.2 to 0.5 lb/MMBtu.

Why is Mn is emitted from wood-fired boile rs and not from residential wood stoves? The hypothesis is boilers are very efficient and the particulates being emitted are mostly inorganic combustion products. In wood stoves the particulates are primarily recondensed organics and most of the metals stay in the bottom ash. This was supported in discussions with the consultant that did much of the AP-42 technical report and other studies (29 & 30) and with ORD’s w ood stove contacts in NRMRL in NC. This also explains why there is not seasonal differences in ambient air levels where

there is considerable re sidential wood burning.

This leaves the question about wildfires. Very little data were found initially on metal

emissions from wildfires. Two recent sources indicate that wildfires do not contribute the

same level of Mn to the air as wood-fired boilers. Region 4 EPA partnered with ORD’s NRMRL to have the region’s lab run Mn anal ysis on samples that were taken, but not analyzed, for a study on particulate emission from burning of Foliar Fuels (31). The data from these sample analysis were com pared to the fuel mass and air flow to

determine actual mass emission rates for MN. These data indicate higher mass emissions on Mn from eastern species of trees, like Duke Forest (mixed) and Loblolly(414 and 546 ug/kg) and lower levels for western trees like Hemlock and Ponderosa (166 and 119 ug/kg). This study did not measure heat generated in these experiments. Therefore in order to get an approximation of emission factors an assumption of the residential fireplace was utilized to get emission rates in the AP 42

format of lbs/MMBtu. Heat generated would have to be ve rified before claiming these as reasonable emission factors but, even with some uncertainty the conversion24 indicates that emission factors are closer to wood stoves (1.3 to 6.3 X10-5 lb/MMBtu)

than to wood-fired boilers. The results of this determination is given in table 11.



### Table 11 Manganese Emissions from Burning of Foliar Fuels

Test Date Fuel Mass Mn Conc*. Mn Mass Emission Emission Factor** Kg ug/m3 ug/kg 10X-5 lb/MMBtu

Duke Forest 3/8/00 8. 7 0.15 414 4.786

Hemlock 4/5/00 12.02 0.083 166 1.919 Loblolly 2/11/00 5.8 0.12 546 6.312

Palmetto 8/31/00 11.6 0.098 111 1.275

Ponderosa 7/18/00 8.98 0.041 119 1.375

* Analysis January 2004 by US EPA Region 4 Lab

** Used conversion factor for wood stoves because no caloric measurement was done during original experiment. These data are estimate.

The October 2003 wild fire s in California lead to considerable sampling by local air agencies. The results have been posted on the California Air Resources Board web site and summarized in a report, also on the web site . (35) While Mn was not a metal toxic of concern, there were a number of stations that measured Mn. The data indicate that

ambient Mn levels did not increase much over historic levels and the levels at PM 2.5 did not rise over 50 ng/m3. (highest reco rded was 33 ng/m3) Considering the large increases of PM during these fires, it can be assumed that little of the Mn in the burning wood is getting into the increased PM levels. This low increase in Mn brings into question the assumptions in the Bureau of Mines “Manganese Material Flow Patterns (4).25 Summary

Mn is by far the HAP metal emitted in the greatest amount from wood-fired boilers. It

accounts for over 90% of the HAP metal emissions from burning wood. Most woodfired boilers will be covered by an upcoming MACT standard and will be required to provide particulate control. This will also reduce Mn emissions. The controls will reduce Mn emissions to levels experienced in w ood-stoves and fireplaces. There is need to

determine emission factors for Mn fr om wild fires and prescribed burns.26 

## Manganese Emissions and Air Quality

A final investigative question was going to look into how the emission factors were developed. This was address ed in the previous chapter, so the question was changed

to one that tried to relate Mn emissions to ambient air levels.

Approximately 180 ambient air monitoring sites in the US measure Mn. This data can be accessed via the AIRS-AQS data system. The units of measurement for Mn depend upon the State doing the measurement. T here are three units that the Mn data are presented: (1) the Total Suspended Particulates (TSP) dat a with 80 sites; (2) some 40 sites measuring PM10 and (3) 60 sites m easuring PM2.5. These are the only monitoring sites available in the national system.

South Carolina is the state with one of the most widespr ead monitoring systems in Region 4. They had 30 (all TSP) of the 180 monitoring si tes in the 2000 data set.

Therefore SC was taken as one of the focus ar eas to try to relate reported emissions of Mn in TRI with ambient levels from the many monitoring sites. Two sites in Georgetown SC had average ambient level of 0.1 ug/m3 which is double the EPA reference dose (RfD) of 0.05 ug/m3. Four monitoring sites in Georgetown all had recordable levels of Mn above the RfD. Only two had averages above the 0.1 leve l. These monitoring sites had frequent sampling with each one having over 60 observations.

Reviewing a period from 1995 to 2001, TRI reports indicate only two significant air

releases of Mn from the Georgetown SC area. These were Georgetown Steel and International Paper, Georgetow n Mill. Both these facilities had Title V permits and both permits were reviewed to see how Mn was handled. The TRI data and ambient Mn levels for this period are shown in Table 12. The ambient data shows widespread

elevations of Mn measured as TSP. The TR I data indicates that Georgetown Steel was the major reporter of emissions and that In ternational Paper was only reporting air

emissions of 170 lbs for mo st of the years.

The TRI emissions do not seem to be account able for the high ambient levels at the monitoring stations. One reading was 160 time s the RfD for Mn. Since the acceptable ambient air concentration in SC is 25 ug/m3, this value probably did not raise concern.

It is also of some concern that emission in ventory data that was su bmitted to the state

did not match the data reported to TRI. In 1999 the st ate reported that International Paper’s Mn emissions inventory was 14,300 lbs from their two wood-fired boilers. This was probably an error and their 2001 inventor y reported 2,346 lbs., which is much closer to the TRI reported 1,100 lbs. This highlights the need fo r better coordination

between emission data from different source s. One wonders why the TRI report is not27 used as the emissions inventory data and why a separate number is generated for the permit.

Table 12 Comparison of TRI Air Releases and Ambi ent Mn levels in Georgetown SC TRI in lbs and Mn in ug/m3 (TSP)

Facility/Year 1995 1997 1998 1999 2000 2001

Air emission in Lbs

Geo. Steel 5,900 2, 061 1,102 1,319 1,513 2,291

Int. Paper NR 170 170 180 170 1,100

Monitoring Sta. Ambient air conc in ug/m3

06 Max 8.8 3.2 1.1 0.4 0.4 1.8

06 Ave 0.3 0.2 0.1 0.1 0.1 0.1

02 Max 0.6 1.4 0.4 0.2 0.2 0.4

02 Ave 0.1 0.1 0.1 0.1 <.1 0.1

07 Max <.1 0.2 0.3 <.1 0.3 0.1

07 Ave <.1 <.1 <.1 <.1 <.1 <.1

08 Max 0.1 1.2 0.6 0.4 0.6 0.3

08 Ave <.1 0.1 0.1 0.1 0.1 0.1

A review of their Title V permits revealed the following: International Paper (IP) M ill has two 592 MMBtu/hr boile rs that have cyclone and ESP particulate controls. They are authorized to bur n wood, coal and oil. Wood is reported to be the primary fuel. The permit had a PM lim it of 0.1lb/MMBtu and had specific limits

for six of the ten HAP metals as specified in State Regulati ons. They did not have limits for Mn. It is interesting to note that the sum of these six metal’s c ontent in wood is 3.1 mg/kg while the concentration of Mn is 33.6 mg/kg (see table 8). The permit contained a modeled emission rate for Mn, but this wa s very high (23.6lb/hr) and the State later

said that it should have been a value maximum daily rate of 17 lbs/day (0.71 lb/hr). The amount of wood was required to be reported to the State but was marked confidential

and is not releasable. Further information was obtained from the mill. They used a stack28 emission test from a similar boiler at another IP mill, of 3.25X10-5 lb/MMBtu. This is comparable to NCASI data. The Boiler stacks are 83 meters high and should lead to wide dispersion of emissions. It was concluded that the current repor ting of 1,100 lbs of

emissions is closer to what the mill has been releasing.

The Georgetown Steel Permit does not have any wood-fired boilers nor metal emission limits or monitoring requirements. This fac ility appears to be most closely related to

Steel Foundries. AP42 does not have metal emissi on factors for this type of facility, only PM. The permit did have modeled emission rates for Mn and 3 other HAP metals.

These were:

Cadmium 0.0012 lb/hr

Chromium VI 0.0104 lb/hr Manganese 0.1465 lb/hr

Nickel 0.0007 lb/hr Manganese has a high emission rate compared to the other metals but if the plant operated continuously at this rate the annual em ission would only be 1,283 lbs of Mn. The plant reported 2,291 lbs of Mn air emissions to TRI in 2001.

The remaining monitoring sites in SC were reviewed and sites recording Mn levels had foundries or other metal proces sing facilities. While this was not part of the study it certainly is cause for more investigation.

On the national level the two sites having t he highest ambient levels of Mn were in Marrietta OH and E. Liverp ool OH. Marietta OH is the home of the only Ferromanganese Alloy Plant in the US. It also has the highest reported TRI emissions with 431,600lbs being r eported in 2000. E. Liverpool OH has the highest recorded Mn levels in the nation with average Mn levels at their two stations being 0.7 and 1.5 ug/m3, nearly an order of magnitude hi gher than Georgetown and 2 to 4 times higher than the 0.4 ug/m3 levels the State of Ohio reported from their monitoring si te in Marietta. In E. Liverpool there is no reported TRI releases and in the surrounding county there was only 600 lbs reported in 20 00. E. Liverpool is also home to a Hazardous Waste

Incinerator. Due to claims that the incinerat or was the source of the high Mn levels, a major monitoring study was conducted to det ermine the cause (32). This study, with numerous monitoring stations, determined that the probably source was an unpermitted metal handler near the incinerator. It is surprising that the highest measured ambient levels in the nation are caused by a facility that is not being regulated. The report noted that they felt that the Mn meas ured was mostly larger than the fine level (2.5PM) and did not pose a high risk. Another Health Consultation (33) by ATSDR in Washington County (where Marietta is) also stated that there was not a serious problem

because the levels never exceed the NOEL for Mn. This conclusion has been challenged because the ambient val ues greatly exceeded the RfC.29 Summary

There is not a good correlati on between ambient air concentra tions of Mn and reported TRI releases. There appears to be a lack or coordination between reported emission inventory data and what is being reported in TRI reports. Mini-steel mills and metal foundries need further investigat ion to better estimate emissions of Mn from their operations.



## Manganese Summary and Conclusions

This study was conducted because of three concerns raised by a relative risk study done in Region 4. The concerns were 1. Is Manganese a significant risk in the regi on as reported in the relative risk study? 2. Is Manganese emitted from wood-fi red boilers a significant risk? 3. Is there a possible underreporting of Manganese from these boilers?

These concerns led to a study that in itially focused on wood-fired boilers and investigative questions on how much Manganes e (Mn) is being sent to the boilers, what is happening in the bo ilers and how much is being emitted. This was expanded to determine what role to wo od-stoves and wild fires play in Mn emissions. It was hoped that available studies would show the relationship that soil and ecosystems have in Mn levels in type s of wood used in the wood-fired boilers and potentially determine a way to minimize emissions by type of wood used.

It was determined that Mn does pose a risk to Region 4 because of its very low inhalation Reference dose (RfD). This value (0.05 ug/m3) is low because of a significant safety factor built into the va lue due to the lack of studies on sensitive groups that other hazardous metals have. Mn has not received the level of attention as other hazardous metals ( like Mercury) t hat have less stringent RfDs. As a result

it is not limited and monitored in permits to the level that its low RfD would seem to require. Mn in high exposure is a neurotoxin but not a canc er causing substance. It

is not considered bioaccuml ative but its medical impac ts (Manganism) are reported to continue and progress, after exposure is removed and the body levels are

reduced. This seems worse than bioaccuml ative metals, because it may not be easy to trace medical impacts back to an exposure.30 Wood-fired boilers will not be a significant risk for Mn due to an upcoming Boiler MACT that will control particu lates and therefore Mn emissions. Mn constitutes over 90 percent of the Hazardous Air Pollutant (HAP) metal emissions from wood-fired

boilers. Its concentration in wood is an order of magnitude high er than any of the

other ten HAP metals. The Boiler MACT wil l require tight particulate controls and the post control MN emissi ons will be on the same order of magnitude as woodstoves that have emission estimates two orders of magnitude less that wood-fired boilers. Many current wood-fired boilers in the Paper sector already have Electrostatic Precipitators (ESP) that c an remove particulates by up to 99%.

There is considerable under r eporting of TRI Mn emissions from facilities that have wood-fired boilers. Part of this is caused by the TRI limits before a facility is required to report. This limit of 25,000 lbs is considerably higher th at for some other hazardous metals like mercury and lead wher e the limit is 10 lb s. The furniture industry uses wood-fired boilers and rarely r eport Mn emissions. Their controls were mostly mechanical and the removal effici ency was considerably less than those employing ESPs. Also a number of large bo ilers in the sugar cane industry employ waste cane (Bagasse). The cane also cont ains similar levels of Mn as wood and none of these facilities report TRI emissions. Based on a State of FL estimate of

over 3.8 million tons of B agasse burned and there are pr obably many facilities that are emitting significant amounts on Mn.

While outside the scope of this study, the Mn emissions fr om mini-steel mills and

foundries need to be evaluated to better esti mate their air emissions. Disparities between ambient air Mn levels and reported TRI releases seems to point to ministeel mills and foundries as possible sources.

Activities on the initial investigative question s led to mixed results. The first question

was to determine how Mn levels in the wood vary by species and ecosystems. This question was not answered because, while ther e is considerable research on Mn by tree species, pH and available Mn in the soil, the data was reported mostly as Mn

levels in leaves and needles. There is a need to relate the levels in leaves to bark

and trunkwood concentrations.

As to what happens to the Mn in the boile r, it appears than a majority of the Mn is emitted in the Fly Ash as a particulate. Part iculate controls will co ntrol the Mn that is

emitted.

The third question was to review the emi ssion factors. The emission factors published in EPA’s AP42 lumped a number of stack tests that included controlled

and uncontrolled measurements. As a resu lt the factor of 1.6E-3 lb/MMBtu

understates the uncontrolled em ission and overstates the controlled emissions that are in the E-5 lb/MMBtu range.31 The expansion of study to effects on wood st oves indicated that these stoves are

less efficient and most of the Mn remains in the bottom ash. The emission factors for wood stove and fireplaces are in same range as boilers with maximum controls.

Emission factors for wildfires also appear to be less than boilers as indicated by the

California Wildfire data and recent analyses from burning of foliar fuels.

In summary it can be said that Manganese air emissions should receive much more attention than it is presently receiving. There is a definite need to increase medical research into sensitive groups to reduce the uncertainty factors that give Mn such a low threshold for concern. This is especiall y important as the de cision to allow the gasoline additive MMT is being considered.



### Appendix 1

References : Manganese and Wood-Fired Boilers

1. - US Environmental Protection Agen cy, 2002, US EPA Region 4 Relative Risk Initiative, Draft 2002 and not finalized.

2. - Whitten, T., Wolfe, R., 2002, Memo - Relative Risk Initiative - Manganese Compounds in Wood Waste Boilers - Exampl e - Masonite” Internal Memo MS Dept
of Environmental Qualit y, December 17, 2002

3. - National Research Council Committ ee on Biologic Effects of Atmospheric Pollutants, 1973, Manganese, National Academy of Sciences, ISBN 030902143X

4. - Jones, T., 1994. Manganese Material Flow Patterns, Bureau of Mines Information Circular 9399, Dept of Interior. 5. - US Geological Survey, 2003, Manganese Statistics and Information, http://minerals.usgs.gov/mineral s/pubs/commodity/manganese/index.html

6. - Hudnell, K., Mergler, D., 1999, Mangan ese: Essential Element and Neurotoxin, Occupational Medicine Secrets, 1999 Haney & Belfus Inc.32 7 - Centers for Disease Control and Prevent ion, 2003, Candidate Chemicals for

Possible Inclusion in Future Releases of the National Report on Human Exposure to Environmental Chemicals, Federal Regist er Vol. 68 No. 189/ Tuesday September
30, 2003.

8. - Williams-Johnson, M., Altshuler, K., R hodes, S., 2000. Toxicological Profile for Manganese, Agency for Toxic Subst ances and Disease Registry, CDC

9. - Davis, M., and 10 others, 1994, “Reev aluation of Inhalation Health Risks Associated with Methylcycl opentadienyl Manganese Tricar bonyl (MMT) in Gasoline, US EPA ORD, EPA 600/R-94/062

10. - Roels, H., Ghyselen, P., Burche t, J., 1992, Assessment of the Permissible Exposure Level to Manganese in Worker s Exposed to Manganese Dioxide, Neurotoxicology, 20; 255-272 1992

11. - Hudnell, K., 1999, Effects from Envi ronmental Mn Exposures: A Review of the Envidence from Non-Occupational Exposur e Studies, Neuro Toxi cology 20(2-3):379-
398, 1999

12. - Glenn, W., The Heavy Metal Bl ues, 2001, OH&S Canada, Apr/May 2001, Vol 17, Iss. 3 pg.22

13. - Masters, R., Hone, B., Doshi, A., Environmental Po llution Neurotoxicity, and Criminal Violence, 1997, In Rose, J (e d): Environmental Toxicology, London, Gordon, and Breach, 1997

14 - Huang, C., Chu, N., Lu, C., et al . 1998, Long-term prog ression in chronic manganism. Ten years of follow- up, Neurology 50:698-700, 1998

15. - Zekri, M., Obreza, T., 2003, Plant Nu trients for Citrus Trees, SL 200 Univ of Florida Extension, http://edis.ifas.ufl.edu , January 2003

16. - ____ 2001, Manganese in Soils, Fact Sheet from Incitec Fertilizers, Queensland, Australia

17. - _______ 2001, Soil and Plant Nutrition- Manganese, Tree Fruit Research & Extension Center, Washi ngton State University

18. - Sadowski, A., et al, 1980, Effects of Different Levels of Manganese and Boron upon the Nutrient Status and t he Incidence of Internal Bark Necrosis in Apple Trees, ISHA, 92:378-378, 198033 19. - Tracy, J., 1991, Manganese Toxicity in Avocado, California Avocado Society 1991 Yearbook 75:147-158, 1991

20.- Gower, S., 2001. Manganese Deficiency of Fr aser Fir, Michigan State University

Extension.

21.- _______ ____ Plant Analysis and Fert ilizer Recommendations- Walnut, K Ag Labs, http://www.kaglab.com/walnut/plnanly.htm

22.- Hiltbrunner, E., Fluckiger, W., 1995, M anganese deficiency of silver fir trees (Abies alba) at a reforested site in the Jura mountains, Switzerland: aspects of cause and effect, Tree Physiology 16, 963-975 1996

23. - American Furniture Manufacturer’s Association, 2003, Manganese Evaluation in Wood Fuel, Report submitted to EPA Do cket Center, October 17, 2003, Docket ID

No. OAR-2002-0058.

24. - Cooper, C., 1999, Background Informa tion on the Sugarcane Industry and Summary of Stack Test Results from Bagasse-Fired Boilers in Florida and Louisiana, University of Central Florida

25. - Wessel, R., Jorgensen, K., 2001, Co mbustion Modeling of Kraft Recovery Boilers and Stoker-fired Power Boilers, Mc Dermott Technology In c. MTI 01-10, 2001

26. - US Environmental Protection Agen cy, 1995, Compilation of Air Pollutant Emission Factors, AP -42, Fi fth Edition, Volume 1: Stationary Point and Area Sources, Chapters 1.6, 1.9, and 13.1 (Wood Residue Combustion, Residential Fireplaces, and Wildfires and Pre scribed Burning), January 1995, http://www.epa.gov/ttn/chief/ap42/

27. - Eastern Research Group, 2001, Backg round Document Report on Revisions to

5 th Edition AP 42 Section 1.6, US EPA Contract No. 68-D2-0160, July 2001

28.- Hassler, C., Anderson, B., Hutchinson, V., 1998 Overview of Wood-Fired Boiler Use in West Virginia, Appalachian Hardwood Center Fact Sheet 16, West Virginia University

29.- Houck, J., Tiegs, P., 1998, Residentia l Wood Combustion Technology Review - Volume 1, EPA-600/R-98-174a, December 1998

30. - Houck, J., Scott, A., Sorenson, J. , Davis, B., 2000, Comparison of Air

Emissions between Cordwood and Wax-Saw dust Firelogs Burned in Residential34 Fireplaces, Proceedings of: AWMA and PNIS International Spec ialty Conference. April 2002

31. - Hays, M., Geron, C., Linna, K., Smit h, D., Schauer, J., 2002, Speciation of GasPhase and Fire Particle Emissions from Burning of Foliar Fuels, Environmental Science & Technology: Vol 36 NO. 11: 2281-2295

32. - Singhvi, Raj, A Final Report on Envir onmental Monitoring in the Vicinity of

VonRoll WTI Incinerator Facilit y, May 2003, OSWER, USEPA, www.epaosc.org/WTI

33. Colledge, M., Freed, J., 2003, Health Consultation Washington County Air Quality, Marietta, Ohio , ASTDR dated August 11, 2003

34. - Kaiser, J., 2003, Manganese: A Hi gh-Octane Dispute, Science Vol 300, 9May2003, www.sciencemag.org

35 – CA Air Resources Board, 2003, Air Q uality and Wildland Fires of Southern California, October 2003, CA Air Re sources Board, December 2003, www.arb.ca.gov



### Additional References

36. - Zekri, M., Obreza, T., 2003. Plant Nutr ients for Citrus Trees, SL 200 of Florida Cooperative Extension Service.

37. - Muse, J., Mitchell, C., 1995, Paper Mill Boiler Ash and Lime By-Products as Soil Liming Materials, Agr onomy Journal Vol 87:432-438 1995

38. - Liard, A., Lessard, R., Desilets, L., 1999, Product from residue: standard setting for alkaline mill residues in Quebec, Pulp Paper Can. 100 (5): T135-137 (May 1999)

39. - Risse, M., Gaskin, J., 2002 Best Management Practices for Wood Ash as Agricultural Soil Amendmen t, Cooperative Extension Se rvice Bulletin 1142, University of Georgia.

40. - Hedberg, E., Kristensson, A., Ohl sson, M., Johnansson, C., Johansson, P., Swietlicki, E., Vesely, V ., Wideqvist, U., Westerholm, R., 2002, Chemical and Physical Characterization of Emissions fr om Birch Wood Combustion in a Wood Stove, Atmospheric Envi ronment 36 ( 2002) 4823-4837

41. - Omni Environmental Services, 1989, De termination of Particle Size Distribution and Chemical Composition of Pa rticulate Matter from Select ed Sources in California,

California State Air Resources Board PB89-23280535 42. - Hubbard, A., 1995, Hazardous Air Emissions Potential from a Wood-Fired Furnace, Combust.Sci and Te ch, 1995, Vol.108, pp 297-309

43. - Mamuro, T., Mizohata, A., Kubota, T., 1979, Elemental Compositions of Suspended Particles Released from Various Boilers, Annua l Report of the Radiation Center of Osaka Prefecture, Vol 20 (1979)

44. - ________, 1997, Toxic Air Contaminant Identific ation List - Manganese, California Air Resources Board, September 1997 p 620-623

45. - US Environmental Pr otection Agency, 2002, Tri-St ate Geographic Initiative, Greenup Industrial Cluster Air Monitoring and Air Modeling Risk Assessments, USEPA Contract 68-W7-0045, June 2002.

46. - Eastern Research Group, 2001, Re sidential Wood Combus tion, Emission Inventory Improvement Program, Volu me III, Chapter 2, January 2001, http://www.epa.gov/ttn/chief/eiip/techreport/

47. - National Institute of Standards and Te chnology and Colorado School of Mines, 2002, Properties of Lead-Fr ee Solders, February 2002, http://www.boulder.nist.gov/

48. - US Environmental Protection A gency, 1999, Compendium of Methods for Inorganic Air Pollutants- Chapter IO-3, June 1999, http://www.epa.gov/ttn/amtic/inorg.html

49. - Sullivan, R., 1969, Preliminary Ai r Pollution Survey of Manganese and its Compounds , Prepared under cont ract # PH 22-68-25 for Public Health Service,

October 1969



### Appendix B Persons contracted during Study of Manganese from Wood-Fired

Boilers

Name Organization Telephone/email

Dave Tingey WED, NHEERL 541-754-4621 William Hogsett WED, NHEERL 541-754-463236 Allison Stock CDC Ags2@cdc.gov

Alden Henderson CDC 404 498-1351 akh0@cdc.gov Stephanie Davis CDC epidemiologist 404 498-0603 sgd8@cd

c.gov

Ken Hudnell RTP, NHEERL 919 541- 7866 hudnell.ken@epa.gov Allison Humphris Region 4 404 562-9122 Jim Little Region 4 404 562-9118 John Ackermann Region 4 404 562-9063 Beth Antley Region 4 404 562-8454 Jackie Lewis Region 4 404 562-9061

Danny France Region 4 SESD 706 355-8738

Mike Wasko SESD - metal 706 355-8821 Jenny Scifers SESD - Inorganic 706 355-8812

John Calcagni WRRC 919 715-6534 Richard Engler OPPTS 202 564-8587

Julia Gaskin Univ GA 706 542-1401 Larry Morris Univ GA 706 542-2532 lmorris@arches.uga.edu

Ashak Jain NCASI- FL 352 331-1745 a_jain@src-NCASI.org

Arun Someshwar NCASI- FL 352 331-1745 ext 226 Larry LaFlure NCASI- COR 541 752-8801

Jim Pinkerton NCASI - RTP 919 941- 6406 Jpinkerton@NCASI.org

Chris Swab OR DEQ 503 229-5661

Roy Huntley OAQ PS (inventory) 919 541-1060 Bob Whalen OAQPS (combustion) 919 541-1045 Jim Eddinger OAQPS (boilers) 919 541-5426 Joann Rice OAQPS (E.Liverpool) 919 541-3372 Nealson Watkins OAQPS (E.Liverpool) 919 541-5522

Dan Hopkins Region 5(GL) 312 886-5994 Thelma TRI Region 5 312 886-6219 Gary Victorine HW Incin. R5 312 886-147937 Raj Singhvi Edison (E.Liverpool) 732 321-6761 Ying Hsu was CA ARB 916 445-4292

now Pechan&Asso c. 530 295-2995 yhsu@pechan.com

Joe Behar ORD- LV 702 798-2361

John Kinsey woodstove std NRMRL-RTP 919 541-4121 Dean Smith (Pulp Mill Std) NRMRL-RTP 919 541-2708 Michael Hays (open burning NRMRL-RTP 919 541-3984

Bill Perdue bperdue@afma4u.org Am Furn Manf Ind. 336 884-5000 www.AFMA4U.org

Jim Houck houck@omni-test.com OMNI Env. Ser 503 643-3788

Ross DuBose SC Air Modeling 803 898-4123

Bob Betterton betterrj@dhec.sc.gov SC Emission Inv 803 898-4292 Allyson Bristow (emissions) IP Georgetown 843 545-2291

Karsten Bauman kb@eas.gatech.edu GA Tech 404 385-0583

Tim Hunt Air Director Am .Forest & Paper 202 463-2588

Cindy Dewulf OH TRI prog 614 644-3606 Mike Kelley OH P2 Prog 614 644-2930

Paul Koval paul.koval@epa.state.oh.us OH Air 614 644-3615 (or 14)

Lisa Corathers( Thomas Jones ret.) USGS MN Spec. 703 648-4973

Jeff Koener FL Air 850 921-9536

Derrick Brown (Canton NC) Blue Ridge Paper 828 646-2318 Darryl Wite Blue Ridge Paper 828 646-6814

John Kennedy Region 9 Air 415 947-4129

Catherine Brown Region 9 Air 415 947-4137