It's a commonly held belief among some in the environmental community that poorer people are subjected to the most polluted and toxic environments. But a new study suggests all Americans, rich and poor, have their share of toxins; where they are on the income ladder simply determines which poisons are in their bodies.
Using data from the Centers for Disease Control, researchers from the U.K.'s University of Exeter studied the associations between U.S. adults' incomes and levels of 179 toxins. The researchers found that, among 18 toxins that appeared to be associated with income, half were more likely to be present in richer Americans than those at the bottom of the socioeconomic spectrum. That outcome came as a surprise to the scientists who conducted the study.
"We expected chemicals to associate with socioeconomic status, but we anticipated that the majority of chemicals would be higher in poorer individuals," says Jessica Tyrrell, one of the study's authors, in an email to U.S. News.
Tyrrell and her team found that poor Americans tended to have higher levels of lead in their systems than their richer counterparts, which could come from a wide variety of factors, including the air and water, as well as low-income jobs, which are more likely to be industrial and expose workers to lead. Lower-income Americans were also likely to have higher levels of cadmium, potentially a result of smoking, diet, or working in industries like construction and manufacturing. Other toxins more likely to show up among this population were antimony, a metal that people might pick up via smoking or at work, and several toxins found in plastics.
Yet it appears that being wealthier doesn't necessarily mean fewer toxins – in fact, habits considered healthy like eating more vegetables and wearing sunblock appeared to increase toxin levels among richer people.
Wealthier Americans are more likely to have mercury and arsenic in their systems, which the authors said may be attributable to fish and shellfish consumption, though dental fillings may also have led to higher mercury levels. They also found that richer people tend to have higher levels of caesium and thallium, which are associated with home-grown produce. They also have higher levels of PFCs, compounds people might pick up via waterproof fabrics, as well as fresh meat, fish, and other fresh vegetables. Higher-income people, the researchers noted, are more likely to both grow produce and eat those foods. In addition, wealthier people had higher levels of a toxin called BP3 that is found in sunscreens.
This may mean rethinking long-held beliefs about who needs to worry about the health effects of their environment, says Tyrrell.
"Our results suggest that regardless of socioeconomic status, chemicals accumulate in the body. ... Therefore, in the case of chemical burden, everyone needs to be considered, not just those living in poverty," she says.
Despite these results, special attention will still need to be paid to low-income communities, says one expert.
"Nobody is saying that everyone else isn't exposed to chemicals. We all know that," says Albert Huang, a senior attorney at the Natural Resources Defense Council who specializes in environmental justice.
However, he adds that lower-income communities may have a tougher time escaping those toxins. He says everyday products, like foods and cosmetics, are likely to affect a wide swath of society, but higher-income people are generally less likely to work or live in areas where toxin-heavy industries like chemical refining are prevalent. While it's tough to change one's surroundings, avoiding toxic products is easier with a bit more money, he adds, as more expensive versions of products like sunscreen or cosmetics that contain fewer toxins are available.
"There's everyday products which we're all striving to eliminate from commerce so people, no one gets exposed to them, but then there are industrial toxic exposures on top of that that vulnerable communities are exposed to, especially communities of color and low-income," he says.