# Presentation: 042687

## Chemicals of Emerging Environmental Concern: The New Pollutants

- Herb Buxton
- USGS Toxic Substances Hydrology Program

**Notes:**
USGS – Who we are –
Responsibility of being an objective science agency. (carefully consider the experiments you think are important, the compounds you choose to study, non-detections are as important as detections).

## What are we talking about?

- and enter the environment in amounts that may be an environmental health concern.

- Chemicals we use or consume daily at home or at work can be concentrated in the waste stream

## Chemicals of Emerging Environmental Concern (ECs)?

- Vet. Drugs
- Antibiotics
- Hormones
- Steroids
- Detergents
- Plastics
- Antioxidants

- Fire retardants
- Disinfectants
- Fumigants
- Fragrances
- Insect Repellants
- Adjuvants/Inerts
- Degradation or treatment byproducts

## How important is this?

- Some elements of _**potential**_ concern are clear.
- Additional research is needed.
- Increased understanding of how we interact with our environment can guide our actions.

## Why the sudden interest?

- Clofibric Acid found in Swiss Lakes and the North Sea.

*Buser, et al, 1998.*

**Notes:**
Clofibrate – lowers blood cholesterol and triglycerides among other uses.

## Do ECs enter the Environment? 

- Do ECs enter the Environment?

- National Stream Reconnaissance

- (Kolpin, et al., 2002)

**Notes:**
The initial fundamental question we attempted to answer was to simply to determine if CECs are present in the environment. This basic question was answered through our national stream reconnaissance study that was published in 2002. Through this study we examined a set of 139 streams across 30 states. This study found that, in fact, chemicals we use in our daily lives can be concentrated in the waste stream and enter the environment in amounts that may be of an environmental health concern.

## Human Waste Pathways

- CSOs
- ISDS
- Industrial Disch.
- Landfills
- Water Reuse.

**Notes:**
Pico Rivera 130 Mgal/d over 1,000 acres.

## Aquatic and Terrestrial Sources!

- _Aquatic _
- - low levels (ppb)
- - continual release

- _Terrestrial _
-  higher levels (ppm)
-  episodic release

**WWTP**

**Notes:**
Biosolids 8 M Tons dry weight annually in US and 40-50% is land applied.

A WWTP has both liquid and solid waste treatment and disposal. The treated liquid effluent is commonly discharged continually into surface water bodies (such as in the picture on the left). Concentrations of CECs in such effluent generally range to sub-ppb to ppb levels. Conversely many CECs are selectively removed from the liquid waste during treatment and concentrated into the sludge or biosolids. In a recently published USGS study we found that many CECs are present in biosolids in ppm levels (orders of magnitude higher concentrations than generally found in treated effluent). However, there release are generally episodic in nature as these biosolids are just periodically applied to the land surface as source of plant nutrients. Thus, CECs in such biosolids after land application could runoff to streams or infiltrate to groundwater. In addition, this leads to exposure of terrestrial organisms (such as earthworms). These very different pathways lead to substantially different transport and exposures to CECs.

## Animal Waste Pathways

- Animal Agriculture
-  Waste lagoons
-  Land application
-  Processing
-  Aquaculture

**Notes:**
450,000 AFOs in the US.
Perhaps thousands of animals per facility.
Each animal may receive therapeutic dose.
Another potential source of pharmaceutical compounds and hormones to the environment is confined animal feeding operations. These facilities use significant quantities of antibiotics and growth regulators. In addition, the animals themselves produce biogenic hormones. Normalized to manure production, hogs produce about 2.5 times as much waste and cattle produce about 20 times as much waste as humans. As a consequence, a typical hog farm, which can hold 1 million animals, potentially has the impact of a city of 2.5  million, and a cattle operation of the same size would be equivalent to a city of 20 million. This is particularly significant when the fact that most such operations are located in rural areas with a much smaller human population.

Iowa tile drain 422250093231801 (TC240, county tile to Tipton Creek). This tile drains about 6,000 acres of cropland. Flow was about 4 cfs at the time of water sampling. Site is instrumented by USDA – ARS.

## PBDE’s in Soil near Weathered Outdoor Computer Scrap

- PBDEs measured in soil and sediment as high as 1500 ppb  (PBDE 183)
- Sediment transport to the adjacent stream.
-                   (Orazio et al., 2006)

**Notes:**
Tetrabromobisphenol-A (TBBPA) & polybrominated diphenyl-ethers (PBDEs) are major brominated flame retardants in electrical and electronic equipment (EEE), constituting about 1% of EEE plastic mass. Penta, Octa and Deca added to numerous polymers since the 1970’s.

They have been used in a wide array of household products, including fabrics, furniture, and electronics. There are three main types, referred to as penta, octa and deca for the number of bromine atoms in the molecule. After studies in Sweden found substances related to PentaBDE accumulating in breast milk and other tissues, Sweden reduced the use of this substance 

At This site, Approx 50,000 scrap computer systems, exposed to the outdoor elements four to five years. 3- 4 acres (~1 hectare) of computer scrap, located in rural central Missouri farmland, USA. computers, printers, CRT monitors, and electronic typewriters ranging from late 1970’s to late 1990’s models. The edge of the piles was as close as 5 meters from the stream. Annual rainfall 90 cm. Sunny summer of 30-40 °C. 

## National Surveys

## Don’t look just in the water!

**Notes:**
If you take a look at this graph, you can clearly see the multi-media aspect of CEC occurrence that I just mentioned. This graph represents a set of pharmaceutical compounds that were measured in both stream water and stream sediment. There’s numerous pharmaceuticals on this graph (ranging from antibiotics to heart medications), but I want you to just look at the broad patterns in the blue and red bars. Compounds on left were more frequently detected in stream water; compounds on right were more frequently detected in stream sediment; and those compounds in the middle were associated with both water and sediment. 

In particular, you can see that carbamazepine (a drug used for epilipsy and bi-polar disorder) is frequently detected in both stream water and stream sediment. Thus, there are multiple potential routes of exposure to aquatic organisms for this compound. On the other hand, if you look at the 3rd compound from the right -  fluoxetine (an antidepressant more commonly known as Prozac), you can see that there were no such detections in water. Thus, with only this information one could conclude that this compound is not an issue in streams. However, Dr. Bryan Brooks at Baylor University, has found that all fish in a stream they examined in Texas had fluoxetine present in their tissue. So where is the exposure to this compound coming from? Well, going back to this graph when stream sediment is considered, we see that, in fact, about a quarter of the streams sampled had detections of this compound. Thus, the sediment data helps us understand potential additional exposure pathways for aquatic organisms. Thus, to completely understand both environmental occurrence and ultimately environmental effects, both media needs to be examined.

## What have we learned about CECs?

- Present at _*sub-ppb concentrations*_ in water.
- 		- Streams and Groundwater
- Present as complex _*mixtures*_.
- Reflect a wide range of _*human activities*_.
- Some compounds _*mobile and persistent*_.
- Present in various _*environmental*__ __*media*_ (water, solids, tissue) sampled.

**Notes:**
Over the last 8 years of conducting CEC research, the major lessons the USGS has learned are that indeed these compounds are present in low concentrations in water. Through a series of national-scale studies on susceptible waters, we found that about 80% of the streams and aquifers sampled had at least one CEC detected. Because of the longer pathways, however, we generally find lower concentrations in groundwater compared to streams. Research by other agencies has found CECs to also be present in marine and coastal waters as well. CECs are present in the environment as complex mixtures. Rarely do we find only a single compound in a given water sample. During our national stream study, a median of seven compounds were found in the streams sampled with as many as 38 compounds detected in a single stream sample. This is an important finding as it documents the simultaneous exposure of organisms to a wide variety of compounds. The CECs found in the environment reflect a wide range of human activities. The types of compounds found range from pharmaceuticals we use for medicinal purposes, fragrances to that keep us smelling nice and fresh, natural occurring compounds such as cholesterol, to chemicals we use on livestock and pets for various purposes. The results of our research and research done by others, documents is that in reality anything we use has the potential to become an environmental contaminant. Select compounds are both mobile and persistent. This, however, is very compound specific and depends on such factors as their chemical and physical properties. For example, compounds such as carbamazepine (which is an anti-epileptic drug) have been found to be quite resistant to natural processes such as biological and chemical degradation. Thus, once input into the environment, these persistent compounds can be transported long distances along both surface and subsurface pathways. Conversely, other compounds such as tonalide (a musk fragrance) seem to have fairly rapid reductions in concentrations as they are transported through the environment. What CECs we find depends on the media being sampled. 

## Ecological Concerns

- Uptake in Organisms
- Endocrine Disruption
- Antibiotic Resistance
- Pathogens
- Other Ecological Effects

**Notes:**
Ecological concerns can be divided into these broad categories: Uptake in organisms including both plant and animals. For example on the terrestrial side, we’re examining worms in fields where biosolids and animal manure have been applied to determine if CECs are being biomagnified in worm tissue. As worms area basic food source for many animals, a longer-term research goal is to determine if worms are also a mechanism for CEC exposure to higher organisms. As Jeff discussed in the previous talk Endocrine disruption is also a concern. Antibiotic resistance is another concern as such resistance decreases the effectiveness of current medications control bacterial infections in both human and animals. Thus, the question is whether a mechanism for developing microbial resistance is from the release of antibiotics to the environment. And finally other ecological effects. For example as antibiotics are specifically designed to kill bacteria, their presence in the environment could change indiginous microbial populations which may have an effect on natural soil function. 

## Antibiotic Resistance

- Direct use in orchards.

- Resistance develops in organisms.
- Environmental transfer of resistance genes.
- Multiple resistance.
- Resistance from non antibiotics.
- Resistance from chronic low-level                                exposure?

- Aquaculture

- Animal waste lagoons

**Notes:**
Topic A: Associating bacterial pathogens and their antibiotic resistance with environmental influences.

Selected antibiotics are used directly in fruit-production agriculture, where they are used to combat bacterial disease of apples and related fruit.  Although apples and other fruit have been documented to transfer devastating bacterial pathogens such as E. coli O157:H7 to products such as cider, little is known about the occurrence or abundance of bacteria that cause human disease (pathogens) on fruit, or about the effects of antibiotic application to fruit on the antibiotic resistance of such bacteria. Using traditional and modern microbiological techniques, this project is determining

the types of bacteria on fruit;
their antibiotic resistance patterns and;
the presence of genetic elements that may allow transfer of antibiotic resistance between different bacteria

The information we provide clarifies the potential food safety hazard associated with the application of antibiotics in orchards.  Our data on antibiotic resistance will help to clarify the environmental factors that drive the acquisition and maintenance of antibacterial resistance genes in bacterial hosts, and the relative risk of their transfer to human pathogens. 

## Endocrine Disruption 

- _Hormones_ – The bodies chemical messengers.
- _Endocrine Disruptors_ – biogenic or synthetic hormones or mimics or blockers that interfere with the message.
- _Observing Effects_ – Intersex (vitellogenin, cellular abnormalities); behavioral responses; population effects (sex ratios)

**Notes:**
In recent years, some scientists have proposed that chemicals might inadvertently be disrupting the endocrine system of humans and wildlife. A variety of chemicals have been found to disrupt the endocrine systems of animals in laboratory studies, and there is strong evidence that chemical exposure has been associated with adverse developmental and reproductive effects on fish and wildlife in particular locations. The relationship of human diseases of the endocrine system and exposure to environmental contaminants, however, is poorly understood and scientifically controversial (Kavlock et al., 1996, EPA, 1997).  -  USEPA

The endocrine system regulates all biological processes in the body from conception through adulthood and into old age, including the development of the brain and nervous system, the growth and function of the reproductive system, as well as the metabolism and blood sugar levels. The female ovaries, male testes, and pituitary, thyroid, and adrenal glands are major constituents of the endocrine system. 
The Endocrine Disruptor Screening Program (EDSP) focuses on the estrogen, androgen, and thyroid hormones. Estrogens are the group of hormones responsible for female sexual development. They are produced primarily by the ovaries and in small amounts by the adrenal glands. Androgens are responsible for male sex characteristics. Testosterone, the sex hormone produced by the testicles, is an androgen. The thyroid gland secretes two main hormones, thyroxine and triiodothyronine, into the bloodstream. These thyroid hormones stimulate all the cells in the body and control biological processes such as growth, reproduction, development, and metabolism. For additional information on the endocrine system and endocrine disruptors, visit the Endocrine Primer. 

## Stewardship

## Drug Disposal

- Whitehouse, Office of National Drug Control Policy – February 2007
- Drug Take-back Programs across the Nation

- http://www.whitehousedrugpolicy.gov/

## Good Practices

- Chemical labeling provides current information useful for avoiding environmental effects.
- Equipment wash water disposal
- Chemical storage and disposal guidelines.
- Informed investments can save resources tomorrow.

## Improved Treatment

- Informed Decisions Regarding Wastewater and Drinking Water Treatment result in wise investments

## Thank you!

- toxics.usgs.gov
- hbuxton@usgs.gov