Even though this EcoNews article is about air poisons that result from fossil fuel production, it applies to just about any combustion source, including cement plants, manufacturing plants, vehicles, and so on. It's a pretty good top ten list, although you wonder why Dioxins and Furans got left off, since they're toxic by the gram instead of pound. Also missing is Particulate Matter as a stand alone threat, although it gets a shout out as a by-product. Nevertheless, these are the among the most dangerous pollutants that have caused and are still causing a lot of problems in North Texas and elsewhere:
Benzene is a well-established carcinogen with specific links to leukemia as well as breast and urinary tract cancers. Exposure to benzene reduces red and white blood cell production in bone marrow; decreases auto-immune cell function (T-cell and B-cells); and has been linked to sperm-head abnormalities and generalized chromosome aberrations.
Benzene is one of the largest-volume petrochemical solvents used in the fossil fuel industry. It is a major component in all major fossil fuel production: oil, coal and gas. People are exposed to it from inhaling automobile exhaust and gasoline fumes, industrial burning such as oil and coal combustion, and exposure to fracking fluids.
There's a recent Emory University study concluding that risk for leukemia fell with every mile between a person's home and facilities that release benzene.
2. & 3. Sulfur Dioxide (SO2) and Nitrogen Oxides (NOx)
Sulfur dioxide (SO2) and nitrogen oxides (NOx) are two primary examples of particle-forming air pollutants (particulate matter). Particulate matter is known to contribute to serious health problems, including lung cancer and other cardiopulmonary mortality. SO2 and NOx are both highly toxic to human health, and contribute directly to thousands of hospitalizations, heart attacks and deaths annually.
SO2 is particularly dangerous for children. Studies correlate SO2 emissions from petroleum refineries—even in lower exposure levels over time —to higher rates of childhood asthma in children who live or attend school in proximity to those refineries. Similarly, small particles of NOx can penetrate deeply into sensitive lung tissue and damage it, causing premature death in extreme cases. Inhalation of such particles is associated with emphysema and bronchitis.
4. Petroleum Coke (Pet Coke)
Pet coke is a by-product of oil processing that's also used as a fuel. It's a heavy dust which resembles coal. It's burned in power plants and cement plants. It contains dozens of dangerous chemicals and heavy metals, including chromium, vanadium, sulfur and selenium. It's a huge contributor to particulate mater and NOx and SOx formation
Formaldehyde is a carcinogen with known links to leukemia and rare nasopharyngeall cancers, according to the International Agency for Research on Cancer. Formaldehyde is highly toxic regardless of method of intake. It is a potent allergen and genotoxin. Studies have linked spontaneous abortions, congenital malformations, low birth weights, infertility and endometriosis to formaldehyde exposure. Epidemiological studies link exposure to formaldehyde to DNA alteration. It is also contributes to ground-level ozone.
Independent studies, have detected dangerous levels of formaldehyde in both wastewater and ambient air emissions from fracking operations. One researcher, with the Houston Advanced Research Center, said reading from one test site in North Texas, “astoundingly high,” and, “I’ve never heard of ambient (formaldehyde) concentrations that high… except in Brazil.”
6. Polycyclic Aromatic Hydrocarbons (PAHs)
In actuality, this is not a single listing—polycyclic aromatic hydrocarbons (PAH) is an entire class of toxic chemicals, linked together by their unique chemical structure and reactive properties.
Many PAHs are known human carcinogens and genetic mutagens. In addition, there are particular prenatal health risks: prenatal exposure to PAHs is linked to childhood asthma, low birth weight, adverse birth outcomes including heart malformations and DNA damage.
Additionally, recent studies link exposure to childhood behavior disorders; researchers from Columbia University, in a 2012 Columbia University study, found a strong link between prenatal PAH exposure and early childhood depression. Infants found to have elevated PAH levels in their umbilical cord blood were 46% more likely to eventually score highly on the anxiety/depression scale than those with low PAH levels in cord blood. The study was published in the journal Environmental Health Perspectives.
Mercury is a dangerous neurotoxin emitted from coal-fired power plants and any other combustion source using coal for fuel – like the Midlothian cement plants. It damages the brain and the nervous system either through inhalation, ingestion or contact with the skin. It is particularly dangerous to pregnant women and children. It is known to disrupt the development of the in-vitro brain. In low doses, mercury may affect a child’s development, delaying walking and talking, shortening attention span, and causing learning disabilities. High dose prenatal and infant exposures to mercury can cause mental retardation, cerebral palsy, deafness and blindness. In adults, mercury poisoning can adversely affect fertility and blood pressure regulation and can cause memory loss, tremors, vision loss and numbness of the fingers and toes.
One out of every six women of childbearing age in the U.S. have blood mercury levels that could be harmful to a fetus, according to EPA reports. The EPA estimates that 300,000 children are born each year at risk for significant development disorders due to mercury exposure.
8. Silica (Silicon Dust/Sand)
Crystalline silica (“frac sand”) is a known human carcinogen; breathing silica dust can lead to silicosis, a form of lung disease with no cure. This is a hazard in the cement industry and threat to those living downwind of cement plants, and now it appears to be one for natural gas roughnecks and adjacent homeowners as well.
Silica is commonly used, in huge amounts, during fracking operations. Each stage of the process requires hundreds of thousands of pounds of silica quartz–containing sand. Millions of pounds may be used for a single well.
The presence of silica in fracking operations, simply put, is a major safety risk with a high likelihood of dangerous exposure. Case in point: researchers from the National Institutes of Occupational Safety and Health (NIOSH) recently collected air samples at 11 fracking sites in five different “fracking states” (CO, ND, PA, TX and AR) to evaluate worker exposure to silica. Every single site had measures higher than the NIOSH threshold for safe exposure—so high, in fact, that about one-third of the samples collected were even above the safe threshold for wearing a safety respirator mask. This was reported in May 2013 in the Journal of Occupational and Environmental Hygiene.
Radon is a colorless, odorless, tasteless radioactive gas which causes lung cancer. It is the second largest cause of lung cancer in the U.S. after cigarette smoking. About 20,000 people per year die from lung cancer attributed to radon exposure according to the National Cancer Institute. Further, there is no known threshold below which radon exposures carries no risk.
Radon exposure can come from a variety of natural sources. However, fracking (natural gas) represents a significant new and increased source of radon exposure to millions of citizens. Radon is released into local groundwater and air during fracking operations. It also travels through pipelines to the point of use—be it a power plant or a home kitchen.
The science behind radon release and exposure is complex but explained well here by Christopher Busby, the Scientific Secretary of the European Committee on Radiation Risk, who warns that radon dangers from fracking “have not been addressed properly (or at all) by the environmental impact statements published by the operators, or by the Environmental Protection Agency in the USA.”
10. Hydrofluoric Acid (HF) / Hydrogen Fluoride
Hydrofluoric acid (HF) is “one of the most dangerous acids known.” HF can immediately damage lungs, leading to chronic lung disease; contact on skin penetrates to deep tissue, including bone, where it alters cellular structure. HF can be fatal if inhaled, swallowed, or absorbed through skin.
The senior laboratory safety coordinator at the University of Tennessee said, “Hydrofluoric Acid is an acid like no other. It is so potent that contact with it may not even be noticed until long after serious damage has been done.”
Hydrofluoric Acid is a common ingredient used in oil and gas extraction.
Numerous studies, including recent ones conducted by both The Center for Public Integrity (CPI) and the United Steelworkers Union (USU) cite the oil industry’s abysmal safety record as a high risk factor for a major HF accident; over the past decade, more than 7,600 accidental chemical releases from refineries have been reported by the industry. In the past three years alone, a total of 131 “minor” accidents involved HF.
Spurred by recent studies in Germany and France that found children living near certain nuclear reactors were twice as likely to develop leukemia, NRC commissioners are considering undertaking one of the largest epidemiological studies ever considered, proposing to examine cancer rates of those living adjacent to or near all 104 American nukes.
According to the agency, about 1 million people live within five miles of operating nuclear plants, and more than 45 million live within 30 miles. The Comanche Peak nuclear power plant in Glen Rose is about 40 or so miles southwest of Ft. Worth. It actually sits partially in Hood County, which is north, or downwind, of the nuke most of the year. Hood County has seen its cancer rate "increase significantly" since the plant came online and posted a cancer mortality rate higher than more heavily-populated and polluted Tarrant County, according to one activist who looked at the state-collected data.
The challenges to doing this kind of unprecedented study well are vast. There are problems with population mobility, uncontrolled variables, and lack of appropriate data. Nevertheless, the NRC seems to be at least seriously considering the idea:
"The five-member NRC is expected to vote later this year on a proposal to investigate cancer rates in each census tract within a 30-mile radius of a nuclear reactor and assess cancers in children younger than 15 years old by reviewing their mothers' proximity to a nuclear facility during pregnancy. It would also review cases of leukemia, a cancer associated with radiation exposure of children."