# SYNOPSIS
This report reviews available scientific and technical information on furfuryl alcohol and recommends a standard for the control of furfuryl alcohol hazards in the workplace.
The acute hazards include eye, skin, and upper respiratory irritation from direct contact and depression of the central nervous system from inhalation or percutaneous absorption. Evidence of a chronic effect is not available.
Other hazards associated with the compound include combustibility and violent reactivity when mixed with aci d s .
About 9,000 workers are potentially exposed to furfuryl alconol in the United
States, and about 100 million pounds are produced and used each year.
Its main use is in the synthesis of furan resins, wnicn are used m such operations as the binding of foundry core sand.
In the absence of data indicating that the existing permissible limit is not protective, the standard proposed to the US Department of Labor contains recommendations for continuation of the present Federal limit of 200 mg/cu m as a time-weighted average concentration and also for a program of medical and environmental surveillance.
Based in part on information gathered from plant site visits and reviewer comments, work practices are recommended to reduce fire and explosion hazards and to minimize skin contact.
Requirements for posting and labeling, a respiratory protection program, an education program for employees, and the maintenance of relevant records are also included.
Suggested research to correct deficiencies m available information includes:
(1 ) epidemiologic studies of employees exposed to furfuryl alcohol; (2 ) animal studies of any chronic effects of furfuryl alcohol, including experimental studies of its possible carcinogenicity;
(3 ) possible effects on reproduction, including whether or not furfuryl alcohol can cause terata or induce mutations; and (4) biotransformation of furfuryl alcohol, its distribution, and elimination. Compliance with all sections of the recommended standard should prevent adverse effects of exposure to furfuryl alcohol on the health of employees.
Methods recommended in the standard are measurable by techniques that are reproducible and available to industry and government agencies.
Sufficient technology exists to permit compliance with the recommended standard.
Although NIOSH considers the workplace environmental limit to be a safe level based on current information, the employer should regard it as the upper boundary of exposure, and every effort should be made to maintain the exposure at levels as low as is technically feasible. The criteria and recommended standard will be reviewed and revised as necessary.
This recommended standard for furfuryl alcohol is based on the limited information available on the effects from exposure to furfuryl alcohol. The standard is designed to safeguard workers occupationally exposed to furfuryl alcohol from absorption of the compound, possible subsequent irritation of the skin, eyes, and respiratory tract, from central nervous system (CNS) effects, and from the hazard arising from its violent, possibly explosive, reaction when in contact with acids.
These criteria and the recommended standard apply to occupational exposure of employees to hydroxymethy1 furan, referred to as "furfuryl alcohol." Synonyms for furfuryl alcohol include 2-furylmethanol, 2-furylcarbinol, 2-furan methanol, furfural alcohol, and 2-(hydroxymethyl) furan.
The major industrial use of furfuryl alcohol is in the production of furan resins, which are used as corrosion-and heat-resistant materials, particularly in the foundry industry.
An action level is defined as one-half the recommended time-weighted average (TWA) environmental limit. Occupational exposure to furfuryl alcohol is defined as exposure to airborne furfuryl alcohol above the action level.
Exposures at lower concentrations will not require adherence to the following sections except for 2(a,e), 3(a), 4(a,c), 5, 6(a,d,e,f), 7, and 8 (a). Procedures for the collection and analysis of environmental samples shall be as provided in the appendix or by any other methods at least equivalent in precision, accuracy, and sensitivity to the methods specified.

# Section 2 -Medical
Medical surveillance as described below shall be made available to all employees occupationally exposed to furfuryl alcohol. The employer shall provide information to the physician performing or responsible for the medical surveillance program such as: the requirements of the applicable standard; an estimate of the employee's potential exposure to furfuryl alcohol, including any available workplace sampling results; and a description of any protective devices or equipment the employee may be required to use. (c) Following completion of the examination, the physician shall give to the employer a written statement specifying any condition or abnormality found which would increase the risk to the employee's health by exposure  Respirators specified for use in higher concentrations of furfuryl alcohol may be used in atmospheres of lower concentrations. precautions have been taken to ensure that prescribed procedures will be followed.
Before entry, confined spaces shall be inspected and tested for oxygen deficiency and for the presence of furfuryl alcohol and other known or suspected contaminants such as formaldehyde or phenol.
No employee shall enter any confined space that does not have an entry large enough to admit an employee wearing safety harness, lifeline, and appropriate respiratory equipment as specified in Section 4(b).

# Confined spaces shall be ventilated while work is in progress
to keep the concentration of airborne furfuryl alcohol at or below the recommended environmental limit, to keep the concentration of other contaminants below dangerous levels, and to prevent oxygen deficiency.
Anyone entering a confined space shall be observed from the outside by another properly trained and protected worker. An additional supplied-air or self-contained breathing apparatus with safety harness and lifeline shall be located outside the confined space for emergency use.
The person entering the confined space shall maintain continuous communication with the standby worker.

# (b)
Smoking shall be prohibited in areas where furfuryl alcohol is produced, processed, stored, or otherwise used.
(c) Employees who handle furfuryl alcohol shall be instructed to wash their hands thoroughly before eating, smoking, or using toilet facilities.

# (d)
Facilities such as double lockers should be provided for employees so soiled clothing can be stored separately from clean clothing. animals, described the composition and properties of coffee oil and reviewed previous chemical data on furfuryl alcohol, one of its primary ingredients.
Erdmann  administered furfuryl alcohol (derived from coffee oil) to 14 rabbits weighing 1.37-3.10 kg (sex, strain, and use of controls were not described)
and to 1 female dog of unstated breed weighing 10.61 kg. The rabbits received furfuryl alcohol in 25 or 50% aqueous solutions, 11 by subcutaneous (sc) injection and 3 by gastric intubation, at single doses ranging from 230 to 1,330 mg/kg of body weight.
The sc lethal dose was 526-600 mg/kg.
Lethal amounts produced significant decreases in rectal temperature followed by what was described as respiratory paralysis within 4-24 hours.
In addition to effects on body temperature and respiration, the rabbits showed a pattern of increased mucus secretion, salivation, and lacrimation.
There were also increased frequency of urination and defecation, and, at higher doses, lethargy or sleepiness approaching narcosis, labored breathing, coma, and, terminally, cessation of breathing. A necropsy performed on one rabbit 12 hours after it died revealed no unusual organ changes.
The dog was given furfuryl alcohol as a 50% aqueous solution at a total dose of 520 mg/kg in two sc injections 30 minutes apart . Within minutes after the second injection, sneezing and vomiting began and continued for about 20 minutes and for 2 hours, respectively. Diarrhea, bloody feces, appetite loss, lassitude, and reduction in rectal temperature persisted through the next day. Two days later, however, the dog appeared fully recovered.
Erdmann , in his study of three men (including himself), noted that furfuryl alcohol in small, single oral doses of 0.6-1.0 g in 5% aqueous solution consistently increased the rate of respiration.
In 1927, Okubo  described the results of in vivo and in vitro studies of the effects of pure furfuryl alcohol on mice, rabbits, and guinea pigs.
The mice were injected sc with furfuryl alcohol in physiologic saline (0.5-1.0% solution). At 10 mg/kg, furfuryl alcohol had little or no effect, whereas at 50 mg/kg the mice showed marked respiratory depression, weakened reflexes, and disturbed gait but recovered within 4-5 hours.
At 100 mg/kg, furfuryl alcohol was lethal within 3-5 hours, death being attributed to respiratory paralysis. Furfuryl alcohol injected intravenously (iv) at unspecified doses reportedly inhibited respiration and also reduced blood pressure in urethane-anesthetized rabbits. No effects from ingestion of furfuryl alcohol at these levels were reported.
A dog was given furfuryl alcohol, 1 g/day, by stomach tube for 42 days. After a 1-month recovery period, the animal then received furfural, at 1 g/day, by stomach tube for 56 days . The only effect seen was occasional salivation after administration.
No changes were evident during the subsequent 1-year observation period.

# Effects on Humans
Jacobson et al , in 1958, reported the results of experiments conducted on 13 volunteers to determine the odor threshold of furfuryl alcohol.
Each volunteer sniffed geometrically increasing concentrations of furfuryl alcohol.
The median detectable concentration for furfuryl alcohol was 7-8 ppm (28-32 mg/cu m ) .
All volunteers were able to detect the furfuryl alcohol at 10 ppm (40 mg/cu m ) , and they described the odor as "sweet," "alcoholic," or "etherlike." Apol , in 1973, reported the results of a health hazard evaluation conducted by NIOSH at a foundry.
One or two workers on each shift produced cores for iron castings prepared by a two-stage, air-set cure process.
The first stage involved the construction of a large core and required 10-15 minutes; the second, the cure stage, required 45 minutes.
The substances used in the process included a mixture of furfuryl alcohol and paraformaldehyde, a phosphoric and sulfuric acid mixture, and sand. After these substances were mechanically mixed, they were poured into the mold. This process was usually performed at room temperature; however, in cold weather the sand was heated before mixing.
The high temperature of the sand apparently caused the release of furfuryl alcohol and formaldehyde v a p o r s .
During the coremaking and the core-curing stages, air samples were collected with charcoal tubes; all such samplings were repeated when hot sand was used .
The furfuryl alcohol concentration was then determined by gas chromatography.
During the 15-minute core preparation, under normal temperature conditions, the concentration of furfuryl alcohol was 8.6 ppm (34.4 mg/cu m ) . When warm sand was used during the same cure period, the concentration of furfuryl alcohol was 10.8 ppm (43.2 mg/cu m ) . None of the three exposed employees reported any discomfort during those operations. However, when the hot sand was used during the 1 5 -m m u t e core preparation, the concentration of furfuryl alcohol was 15.8 ppm ( 63 This was assumed to ensure an approximate saturated test atmosphere in the chamber that also contained a small quantity of liquid furfuryl alcohol.
The concentration of the vapor, however, was calculated from the mass of compound trapped in a collection bubbler containing glacial acetic acid and from the sample volume as measured by a wet-test meter.
The furfuryl alcohol of the absorbing medium was determined using a titrimetric method.
Thirty rats were divided into five groups of six rats each. Three groups were exposed for 4 hours, and the remaining two groups were exposed for 8 hours to the saturated furfuryl alcohol vapor. The first injection of 100 mg/kg produced only a slight and temporary decrease in the blood pressure and respiration.
After the total dose of furfuryl alcohol exceeded 500-600 mg/kg, each injection resulted in a severe drop in blood pressure and in a temporary apnea.
After a total dose of 800-1,400 mg/kg, the animals died from respiratory paralysis.
The No information on human biotransformation of furfuryl alcohol has been found.
The effects of furfuryl alcohol on humans and animals are summarized in Tables II-l, II-2, and II-3.

# Carcinogenicity, Mutagenicity, Teratogenicity, and Effects on Reproduction
No reports were found on whether there are carcinogenic or teratogenic effects from furfuryl alcohol.
There was one report  that indicated that furfuryl alcohol was not mutagenic in tests with Salmonella in vitro. The exothermic hardening reaction increased the evaporation rates of these compounds, and, therefore, the concentrations of their airborne compounds.
The concentrations of these airborne gases were measured in the coremaking areas.
From Sampling can be performed by drawing contaminated air through a collecting device at a measured flowrate that is low enough to ensure complete absorption of the contaminant, ie, the slower the sampling rate, the higher the absorption efficiency should be in any specific system. Furfuryl alcohol can be sampled in at least three kinds of absorbers that use liquid collection media. Simple gas washing bottles, such as midget impingers, may be used, but, since the degree and duration of contact between the sampled air and the liquid are not maximized, it may be necessary to use two or more of these absorbers in series in order to achieve maximum collection efficiency.
Simple gas washing bottles have the advantage of being simply constructed and easy to clean, and they require only a small volume of liquid.
The spiral or helical absorber can also be used for organic vapor collection.
Although it is larger and contains more liquid than a gas washing bottle, its chief advantage is a higher collection efficiency because of the longer contact path between the sampled air and the collection liquid.
Fritted bubblers provide high collection efficiency because of the extensive gas-liquid contact and the low flowrate used (0.5-1.0 liters/minute), but do not have the advantage of small size and volume and ease of cleaning.
Collection of furfuryl alcohol vapor in liquid allows a wide variety of analytical techniques such as oxidation by bromine, polarography, or UV spectrophotometry.
However, the use of a liquid impinger for collection of breathing zone samples is at least inconvenient. Successful use of collectors containing liquids requires careful handling of glassware during collection and shipment of samples to avoid breakage and spillage. Potassium iodide was added to the brominated sample to permit subsequent titration of the liberated iodine.
According to the authors, the overall error of this method is 1%, provided that the total furfural present in the sample does not exceed 20%.
This method has been used to measure furfuryl alcohol in air after sampling at less than 1.5 liters/minute through a fritted bubbler containing glacial acetic acid .
Gas chromatography has become a prevalent method of detection and analysis of organic materials. This technique has been used in the occupational environment  in conjunction with sampling the breathing zone on a solid sorbent followed by carbon disulfide desorption.
Pyridine, however, when used as a desorption solvent, has given excellent desorption efficiencies.
This method has been used to evaluate worker exposure in furfuryl alcohol production facilities . For a 10-liter sample, the lower detection limit of the method was 0.8 mg/cu m, but the authors calculated that by sampling 100 liters of air, this limit would be 0.08 mg/cu m.
Gas chromatography has also been tested with an adsorbent normally used as a column packing for gas chromatographs.
In Therefore, when furfuryl alcohol is handled in an open system, a ventilation system, such as a hood, glove box, or local exhaust system, may be necessary.
In addition, a ventilation system is desirable as a standby if a closed system should fail.
The principles set forth in Industrial Ventilation-A Manual of Recommended Practice  and Fundamentals Governing the Design and Operation of Local Exhaust Systems, ANSI Z9. 1-1971 , should be applied to control atmospheric concentrations and prevent the release of raw materials, furfuryl alcohol products, or wastes during those operations when exposure is possible.
To ensure effective operation of ventilation systems, routine inspection should include face velocity measurements of the collecting hood, examination of the air mover and collection or dispersion system, and measurements of atmospheric concentrations of furfuryl alcohol in the work environment.
Any changes in the work operation, process, or equipment that may affect the ventilation system must be promptly evaluated to ensure that control measures provide adequate protection for employees.
All facilities require frequent inspection and preventive maintenance to ensure that leaks are readily detected and repaired to avoid exposure of employees. Exhaust gases that may contain furfuryl alcohol or hazardous raw materials or wastes should be prevented from being released into the occupational and community environments. In the event of eye contact with furfuryl alcohol, the affected area should be flushed with a copious flow of water followed by appropriate medical attention.
Standard procedures should be formulated for maintenance and repair of engineering control systems; these procedures should not depend on the use of respiratory protection.
There are several essential elements in these maintenance procedures.
Tanks, pumps, valves, or lines must be drained and thoroughly flushed with water or steam prior to repair activities, especially welding, grinding, or other operations that might offer an ignition source for flammable vapor or combustible liquid.
All personnel entering confined spaces must be supplied with whole body protection, such as overalls or impermeable clothing, and suitable respiratory protection in accordance with Table 1
Workers should wear this respiratory protective equipment unless prior measurements indicate that the air concentration of furfuryl alcohol is at or below the recommended TWA concentration limit and that there is an acceptable oxygen concentration (about 20%).
A second properly protected worker must be on standby outside the confined space, and effective communication must be maintained between all involved persons.
A safety harness and lifeline should be used. A monkey exposed to furfuryl alcohol vapor for 6 hours at 1,040 mg/cu m had only very slight lacrimation, but when exposed to 956 mg/cu m for 6 hours/day for 3 days, it showed no effects whatsoever. In addition, dermal penetration has been demonstrated in animals in tests indicative of similar action in humans; it seems from this and from its lipid solvent characteristics (based on its miscibility with such common lipid solvents as ethyl ether mentioned in Table IX Employees should also be instructed as to their responsibilities, complementing those of their employers, in preventing effects of furfuryl alcohol on their health and in providing for their safety and that of their fellow workers.
These responsibilities of employees apply primarily in the areas of sanitation and work practices, but attention should be given in all relevant areas so that employees faithfully adhere to safe procedures.

# (f) Work Practices
Since adverse effects from exposure to furfuryl alcohol are possible by skin 30,32]  For operations that may increase the concentration of airborne furfuryl alcohol in the work environment, adequate ventilation must be used at all times.
Anyone entering the area of an accidental leak or spill must be protectively clothed to prevent accidental contacts with the skin or eyes and must wear suitable respiratory protective devices if needed.    All tubes must be packed with Porapak Q from the same manufacturer's lot.
(2) The smaller section of Porapak Q is used as a backup and should be positioned nearer the sampling pump.
The tube should be placed in a vertical direction during sampling to minimize channeling through the Porapak Q.
(4) Air being sampled snould not be passed through any hose or tubing before entering the Porapak Q tube.
(5) A sample size of 6 liters is recommended.
A  Cap and shake the sample vigorously. Desorption is complete in 15 minutes.
Complete analysis within 1 day after the furfuryl alcohol is desorbed.
(3) Gas Chromatographic Conditions
The typical operating conditions for the gas chromatograph are: 50 ml/minute (60 psig) nitrogen carrier gas flow. 65 ml/minute (24 psig) hydrogen gas flow to detector. 500 ml/minute (50 psig) airflow to detector. 225 C injector manifold temperature. 225 C detector manifold temperature. 200 C column temperature.
A retention time of approximately 11 minutes is to be expected for furfuryl alcohol under these conditions and using the column recommended in Apparatus (d).
The acetone will elute from the column before the furfuryl alcohol.
(4) Injection
The first step in the analysis is the injection of the sample into the gas chromatograph.
To eliminate difficulties arising from blowback or evaporation of solvent within the syringe needle, one should employ the solvent flush injection technique.
The 10-yl syringe is first flushed with solvent several times to wet the barrel and plunger.
Three microliters of solvent are drawn into the syringe to increase the accuracy and reproducibility of the injected sample volume.
The needle is removed from the solvent, and the plunger is pulled back about 0.2 yl to separate the solvent flush from the sample with a pocket of air to be used as a marker. The needle is then immersed in the sample, and a 5-yl aliquot is withdrawn, taking into consideration the volume of the needle, since the sample in the needle will be completely injected.
After the needle is removed from the sample and prior to injection, the plunger is pulled back 1.2 yl to minimize evaporation of the sample from the tip of the needle. It should be observed that the sample occupies 4.9-5.0 yl in the barrel of the syringe.
Duplicate injections of each sample and standard should be made. No more than a 3% difference in area is to be expected.

# It is not advisable
to use an automatic sample injector because of possible plugging of the syringe needle with Porapak Q.
(5) The area of the sample peak is measured by an electronic integrator or some other suitable form of area measurement, and results are read from a standard curve prepared as discussed below.
(e) Determination of Desorption Efficiency (1) The desorption efficiency of a particular compound can vary from one laboratory to another and also from one batch of Porapak Q to another.
Thus, it is necessary to determine the fraction of the specific compound that is removed in the desorption process for a particular batch of Porapak Q.
(2) Porapak Q, equivalent to the amount in the first section of the sampling tube (150 mg), is measured into a 64-mm, 4-mm ID glass tube, flame sealed at one end. This Porapak Q must be from the same batch as that used in obtaining the samples.
The open end is capped with Parafilm. A known amount of a benzene solution of furfuryl alcohol containing 300 mg/ml is injected directly into the Porapak Q with a microliter syringe, and the tube is capped with more Parafilm. The amount injected is equivalent to that present in a 6-liter air sample at the selected level. It is not practical to inject the neat liquid directly onto the Porapak Q because the amounts to be added would be too small to measure accurately.
Six tubes at each of three levels, equivalent to 100, 200, and 400 mg/cu m, are prepared in this manner and allowed to stand for at least overnight to assure complete adsorption of the furfuryl alcohol onto the Porapak Q.
These tubes are referred to as the samples.
A parallel blank tube should be treated in the same manner except that no sample is added to it.
The sample and blank tubes are desorbed and analyzed in exactly the same manner as the sampling tube described in Analysis of Samples.
Two or three standards are prepared by injecting the same volume of furfuryl alcohol into 1.0 ml of acetone with the same syringe used in the preparation of the samples.
These are analyzed with the samples.
and 400 mg/cu m were 1.6% lower than the "true" concentrations for 18 samples.
Any difference between the "found" and "true" concentrations may not represent a bias in the sampling and analytical method, but rather a random variation from the experimentally determined "true" concentration. Therefore, the method has no evident bias.
The coefficient of variation is a good measure of the accuracy of the method, since the recoveries and storage stability were good.
Storage stability studies on samples collected from a test atmosphere at 224.2 mg/cu m indicate that collected samples are stable for at least 7 days.

# Advantages and Disadvantages
The sampling device is small and portable and involves no liquids. Interferences are minimal, and most of those that occur can be eliminated by altering chromatographic conditions.
The tubes are analyzed by means of a quick instrumental method.
One disadvantage of the method is that the amount of sample that can be taken is limited by the mass of furfuryl alcohol that the tube will hold before overloading. When the amount of furfuryl alcohol found on the backup section of the Porapak Q tube exceeds 25% of that founa on the front section, the probability of sample loss exists.
The precision of the method is limited by the reproducibility of the pressure drop across the tubes. This drop will affect the flowrate and cause the measured volume to be imprecise because the pump is usually calibrated for one tube only.

# Apparatus (a)
Personal sampling pump: A calibrated personal sampling pump, the flowrate of which can be determined within 5% at the recommended flowrate.
(b) Porapak Q tubes: Glass tube with both ends unsealed, 8.5-cm long with a 6-mm OD and a 4-mm ID, containing two sections of 50/80 mesh Porapak Q separated by a 2-mm portion of urethane foam.
The adsorbing section of the tube contains 150 mg of Porapak Q, and the backup section contains 75 mg.
A plug of silylated glass wool is placed at each end of the tube. The pressure drop across the tube must be less than 10 mmHg at a flowrate of 0.05 liter/minute.
Immediately prior to packing, the tubes should be acetone rinsed and dried to eliminate the problem of Porapak Q adhering to the walls of the glass tubes.
The Porapak Q tubes are capped with plastic caps at each end.

# Sorbent washing procedure:
Prior to usage, Porapak Q is washed with acetone and dried to reduce or eliminate the effects of unreacted monomers, solvents, and manufacturer's batch-to-batch differences in production. A quantity of Porapak Q is placed in a sintered glass filter fitted to a large vacuum flask.
Reagent grade acetone, of a volume equal to twice that of Porapak Q, is added to the sorbent and mixed, and the pressure is reduced. Repeat the operation of wash-mix-vacuum six times.
The sorbent is then transferred to an evaporating dish and dried in a vacuum oven at 120 C (248 F) under slight vacuum (t>35 mmHg) for 4 hours.

# (c)
Gas chromatograph equipped with a flame-ionization detector. N o t e : Since no internal standard is used in this method, standard solutions must be analyzed at the same time that the sample analysis is done.
This will minimize the effect of known day-to-day variations and variations during the same day of the flame-ionization detector response.

# (a)
Prepare a stock standard solution containing 120 mg/ml of furfuryl alcohol in acetone.

# (b)
From the above stock solution, appropriate aliquots are withdrawn and dilutions are made in acetone.
Prepare at least five working standards to cover the range of 0.12-3.6 mg/1.0 ml.
This range is based on a 6-liter s amp1e .

# (c)
Prepare a standard calibration curve by plotting concentration of furfuryl alcohol in mg/1.0 ml vs peak area.

# Calculations
(a) Read the weight, in mg, corresponding to each peak area from the standard curve.
No volume corrections are needed because the standard curve is based on mg/1.0 ml acetone and the volume of sample injected is identical to the volume of the standards injected.

# (b)
Corrections for the blank must be made for each sample.
mg sample = mg found in front section of sample tube mg blank = mg found in front section of blank tube A similar procedure is followed for the backup sections. T i