Categories
Toxic Tuesdays

Benzo(a)pyrene (BaP)

Toxic Tuesdays

CHEJ highlights several toxic chemicals and the communities fighting to keep their citizens safe from harm.

Benzo(a)pyrene (BaP)

Benzo(a)pyrene (BaP) is a compound in a group of chemicals called polycyclic aromatic hydrocarbons (PAHs). PAHs like BaP are formed in the incomplete burning of coal, oil, gas, or other organic matter. Once formed, they can enter the air, water and soil. The most common way people are exposed to PAHs is by inhaling contaminated air. Vehicle exhaust, wood smoke, asphalt paving and agricultural burning can expose people to PAHs like BaP.

Exposure to BaP for even short periods of time can affect blood cells, leading to anemia and immune system defects. Exposure for long periods of time can affect function of the reproductive system. In studies of laboratory animals, prenatal exposure to BaP impaired learning and memory of offspring.

The most widely known effect of BaP exposure is cancer, and links between BaP and cancer have been known since the 1970s. BaP is one of many components of tobacco smoke that can cause lung cancer. BaP is dangerous because the body converts it into other compounds that can permanently change our cells’ DNA. This can cause cells to function improperly leading to cell death, abnormal cell growth, tissue damage and/or cancer.

CHEJ has previously written about PAHs here.

Learn about more toxics

Categories
Toxic Tuesdays

Polycyclic Aromatic Hydrocarbons (PAHs)

Toxic Tuesdays

CHEJ highlights several toxic chemicals and the communities fighting to keep their citizens safe from harm.

Polycyclic Aromatic Hydrocarbons (PAHs)

Polycyclic aromatic hydrocarbons (PAHs) are a class of chemicals that are formed in the incomplete burning of coal, oil, gas, or other organic matter. They can enter the air, water and adhere to particles in the soil. People are most likely to be exposed to PAHs by inhaling contaminated air. Workers at facilities that produce tar, asphalt, or incinerate trash are at the most risk; community exposure from vehicle exhaust, wood smoke, asphalt paving, or agricultural burning also occurs. Although less common, people can also be exposed by coming in contact with water contaminated with PAHs from discharges at wastewater treatment plants. The US Department of Health and Human Services classifies PAHs as “reasonably expected” to cause cancer. In animal studies, PAHs cause cancer, reproductive dysfunction, and birth defects.

Asphalt shingles are roofing shingles that use asphalt for waterproofing. Because they’re inexpensive and easy to install they are the most widely used roofing covers in the United States, but the asphalt in them contains PAHs. In Wausau, Wisconsin, asphalt shingles waste has been buried as well as left in open-air piles. The grassroots community group Citizens for a Clean Wausau contacted CHEJ about the potential for these waste piles to leach PAHs into the air and soil, exposing surrounding residents. While much is unknown and the situation is ongoing, PAHs can leach out of asphalt at high temperatures and then be dispersed long distances by wind. This means Wausau residents may be inhaling PAHs, elevating their risk for developing cancer. To assess this possibility and the level of risk that may be posed to residents, measurements of contaminants in the shingles as well as in the surrounding air and dust would be necessary. The best way to ensure there is no risk to the community is to remove these shingles and destroy them safely.

Learn about more toxics

Categories
Backyard Talk

New Research: The Hidden Costs of Air Pollution

Exposure to air pollution is linked to a variety of physical health issues, including short-term infections and irritation, and long-term issues like bronchitis and asthma. New research at Columbia University suggests that there may be even more insidious effects of air pollution on unborn children, particularly on their ability to regulate emotions and behavior.

The new study, published in the Journal of Child Psychology and Psychiatry, was the first to look at early-life exposure to PAHs (polycyclic aromatic hydrocarbons) and study its impacts on childhood behavior. PAHs are widespread air pollutants, and are commonly emitted by vehicles, coal plants, industrial manufacturing facilities, and waste incinerators. Due to disparate siting of such facilities in low-income and minority communities, children from these communities are more vulnerable to the impacts of PAHs, which range from cancer to a variety of behavioral issues.

The recent study measured the levels of particular ‘biomarkers’ – compounds that are produced in the body as a result of PAH exposure – in the blood of mothers from New York City. They found that children of mothers with high exposure to PAHs had significantly worse scores on a test that measures behavior and emotional regulation in children. Essentially, PAH exposure may be a predictor of a variety of mental health problems in children and young adults. One study author was quoted in the Columbia Center for Children’s Environmental Health press release:

“This study indicates that prenatal exposure to air pollution…may underlie the development of [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][childhood psychiatric problems] such as ADHD, OCD, substance use disorders, and eating disorders.”

The study particularly focused on women from low-income and minority communities, who are at greater risk of exposure to PAHs. Based on the study, increased exposure to PAHs faced by environmental justice communities may leave the next generation susceptible to not only physical health risks, but also behavioral and emotional issues.

To read more about research at the Columbia Center for Children’s Environmental Health, visit their webpage.

[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]

Categories
Backyard Talk

Study finds risk to children from coal-tar sealants










Children living next to driveways or parking lots coated with coal tar are exposed to significantly higher doses of cancer-causing chemicals than those living near untreated asphalt, according to a study that raises new questions about commonly used pavement sealants.

Researchers from Baylor University and the U.S. Geological Survey also found that children living near areas treated with coal-tar-based sealants ingest twice as many polycyclic aromatic hydrocarbons (PAHs) from contaminated dust tracked into their homes as they do from food.

The peer-reviewed study, and other new research documenting how coal-tar sealants emit high levels of troublesome chemicals into the air, comes as several cities in the Midwest, South and East are trying to ban the products’ use on playgrounds, parking lots and driveways. Some major retailers have pulled the products from their shelves, but coal-tar sealants remain widely available elsewhere.

“There’s been a long-held assumption that diet is the major source of exposure for children,” said Peter Van Metre, a USGS scientist who co-authored the studies. “But it turns out that dust ingestion is a more significant pathway.”

About 85 million gallons of coal-tar-based sealants are sold in the United States every year, mostly east of the Mississippi River, according to industry estimates. The sealants, promoted as a way to extend the life of asphalt and brighten it every few years with a fresh black sheen, are sprayed by contractors or spread by homeowners.

During the past decade, studies have identified coal-tar sealants as a major source of PAHs, toxic chemicals that can cause cancer and other health problems. Pavement sealants made with coal tar can contain as much as 50 percent PAHs by weight, substantially more than alternatives made with asphalt.

Anne LeHuray, executive director of the Pavement Coatings Technology Council, an industry trade group, said she was reviewing the new findings.

“It appears they have some other agenda here, which is to ban coal-tar-based pavement sealants,” she said of the government scientists.

LeHuray and other industry representatives have argued that vehicle exhaust, wood smoke and grilled hamburgers are more significant sources of the toxic chemicals than coal tar.

But the latest USGS research estimates that annual emissions of PAHs from the application of coal-tar-based sealants exceed the amount from vehicle exhaust. Two hours after application, emissions were 30,000 times higher than those from unsealed pavement, one of the new studies found. Parking lots with 3- to 8-year-old sealant released 60 times more PAHs to the air than parking lots without sealant.

By Michael Hawthorne of the Chicago Tribune

The studies are published in the scientific journals Chemosphere, Atmospheric Environment and Environmental Pollution.

[fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][Read more and to download study]

[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]