Melissa Ahern, Martha Mullet, Katherine MacKay, Candice Hamilton
Maternal Child Health, 2010
Keywords: Low birth weight, coal mining, environmental, coal toxicity
Purpose: The authors tested the idea that pregnant mothers who live in coal mining areas are at a greater risk for low birth weight children than mothers in non-mining areas. Previous studies have examined the health effects of coal mining on adults, and this one specifically focuses on newborn children.
Important Finding: Mothers in mining areas have a significantly higher risk of low birth weight, before and after controlling for covariates: "Elevated birth defect rates are partly a function of socioeconomic disadvantage, but remain elevated after controlling for those risks. Both socioeconomic and environmental influences in mountaintop mining areas may be contributing factors."
Significant Quote: “This additional risk for low-birth weight outcomes is not surprising, as proximity in coal mining counties means proximity to environmental contaminants associated with coal mining, cleaning, and transport.”
Results: The researchers used data from the West Virginia Birthscore Dataset and the Department of Energy to look at the effects of coal mining on birth weight of children. Low birth weight is defined as less than 2.5 grams, and it occurs in 5-8% of U.S. births. Unfortunately, in Appalachian coal mining communities mothers are at a significantly higher risk of having children that are underweight. This may be attributed to the pregnant mothers’ exposure to toxins produced by coal mining. Previous studies have shown that low birth weight can be the result of exposure to lead, sulfur dioxide, nitrous dioxide, carbon monoxide, tobacco smoke, and others.
The study looked at 42,770 live births in West Virginia, and it considered whether the child was born underweight and whether they were born in a county with zero, moderate, or high levels of coal mining. The study also considered other variables that affect birth weight, such as the mother’s age, tobacco use, marital status, education, prenatal care, and previous pregnancies.
The study found that mothers in areas with high levels of mining have a significantly higher risk of low birth weight, before and after controlling for these other variables—the odds were 16% higher after adjustment. For example, while the other variables, such as smoking, do have an effect on birth weight, the studies showed that mothers in mining areas still have higher rates of low birth weight after accounting for the variables.
The researchers suggest that future research consider each of these other factors more completely. In addition, they explain that children with low birth weights suffer from problems with IQ and functionality, among other things.
Ahern, M., M. Mullett, K. MacKay and C. Hamilton. (2010) “Residence in Coal-Mining Areas and Low Birth Weight Outcomes.” Maternal Child Health, January 2010.