Chemical safety remains a concern today because the sheer volume of chemicals in commerce has outpaced our ability to evaluate their health effects. Of the roughly 8,600 chemicals actively reported to the EPA, only about 1.8% have undergone formal human health assessments from federal agencies. That gap between what we produce and what we understand about safety defines the modern chemical landscape.
Most Chemicals Have Never Been Fully Tested
The EPA’s Toxic Substances Control Act (TSCA) inventory tracks the chemicals manufactured or processed in the United States. Chemical manufacturing dominates the landscape, accounting for 84% of all reported chemicals across more than 2,200 production sites. Yet federal health assessments exist for a tiny fraction of these substances. The agencies responsible for evaluating chemical risks, including EPA’s own toxicity databases and the Agency for Toxic Substances and Disease Registry, have collectively reviewed less than 2% of the active inventory.
This means the vast majority of chemicals you encounter in consumer products, building materials, and industrial processes have not been formally evaluated for what they do to the human body over time. Chemicals are generally allowed to remain in commerce unless there is specific evidence of harm, rather than being required to demonstrate safety before reaching the market.
Chemicals Already Inside Your Body
One of the clearest illustrations of the problem is PFAS, a group of synthetic chemicals used in nonstick coatings, water-resistant fabrics, and food packaging. The CDC’s National Health and Nutrition Examination Survey has been tracking PFAS levels in blood since 1999, and the finding is striking: nearly all people in the United States have detectable PFAS in their blood. These compounds earned the nickname “forever chemicals” because they resist breaking down in the environment or in the body, accumulating over a lifetime of exposure from drinking water, household products, and food contact materials.
PFAS represent a broader category of persistent chemicals that don’t disappear when you stop using the product that contained them. They move through water systems, settle into soil, and build up in human tissue. The gap between widespread exposure and limited regulation is one of the core reasons chemical safety remains unresolved.
Living Near Industrial Sites Raises Health Risks
Where you live can directly affect your chemical exposure. Research published in the American Journal of Public Health found that children whose mothers lived within one mile of a facility releasing carcinogens during pregnancy had a 72% higher risk of brain cancer. Children who grew up near gas stations or auto repair garages had a fourfold increase in childhood leukemia risk, with one specific type of leukemia showing a nearly eightfold increase.
Respiratory effects are equally well documented. Studies consistently show that living near petroleum refineries, industrial emission sources, and heavily trafficked roads is associated with higher rates of asthma hospitalizations. Short-term spikes in sulfur dioxide from refineries have been linked to increased emergency department visits and hospital admissions for asthma in nearby children. These health burdens fall disproportionately on lower-income communities and communities of color, which are more likely to be located near industrial facilities.
Legacy Contaminants Still in the Ground
Chemical safety isn’t only about new substances. Older hazards persist in infrastructure and soil for decades. The EPA estimates that up to 9 million homes in the United States still receive drinking water through lead pipes, many of them in lower-income communities. A 2024 federal rule now requires replacement of these pipes within 10 years, backed by $15 billion in dedicated funding from the Bipartisan Infrastructure Law and an additional $11.7 billion in drinking water funds that can also go toward lead pipe removal. The EPA estimates the health and economic benefits of this rule are up to 13 times greater than the costs.
Lead is a well-understood toxin. It damages the nervous system, impairs brain development in children, and contributes to hypertension and anemia in adults. The fact that millions of families still drink water flowing through lead pipes in 2024 illustrates how slowly chemical hazards are addressed even when the science is settled.
Accidents Keep Happening
Industrial disasters serve as periodic reminders of chemical risk. In February 2023, a Norfolk Southern Railway train carrying hazardous materials derailed in East Palestine, Ohio. Train cars caught fire and spilled their contents onto the ground, sending chemicals including vinyl chloride into local waterways that carried contamination miles downstream. The National Institute of Environmental Health Sciences launched a research response to assess contamination in soil, water, and sediment, while also collecting blood samples from residents to evaluate long-term liver and other health effects.
East Palestine was not an anomaly. Chemical transport accidents, plant explosions, and storage facility failures occur regularly. Each one exposes nearby communities to substances they had no role in choosing to live near, and the cleanup and health monitoring can stretch on for years.
Workers Bear the Heaviest Burden
More than 1 billion workers worldwide are exposed to hazardous substances each year, including chemical pollutants, dusts, vapors, and fumes. The International Labour Organization estimates that roughly 1 million of these workers die annually from occupational chemical exposure. This makes workplace chemical contact one of the largest preventable causes of death globally, spanning agriculture, manufacturing, mining, construction, and cleaning industries.
Microplastics Carry Chemical Hitchhikers
Microplastics have introduced a new dimension to chemical safety. Plastic is not a single material. It’s a polymer loaded with chemical additives: plasticizers to make it flexible, UV stabilizers to prevent sun damage, flame retardants to resist burning, dyes, lubricants, and heavy metals. When plastic breaks into microscopic fragments, those additives leach out.
Several of these additives are known to interfere with hormones. Bisphenol A (BPA) and phthalates, commonly used in food packaging and household products, are established endocrine disruptors. Heavy metals used as stabilizers and pigments in plastics carry their own risks: lead damages the nervous system and can cause anemia, cadmium disrupts bone metabolism and promotes cancer, and antimony acts as a metallic estrogen linked to breast cancer. Flame retardants containing chlorine and bromine compounds add further toxicity. As microplastics spread through oceans, drinking water, and food, they become delivery vehicles for chemicals that were never meant to be ingested.
Regulation Varies Widely Across Countries
The European Union takes a different approach to chemical regulation than the United States. Under the EU’s REACH regulation, the European Chemicals Agency maintains a Candidate List of substances of very high concern that currently contains 241 entries, with some entries covering groups of chemicals, so the actual number of affected substances is higher. These chemicals face restrictions on use and require companies to communicate their risks to consumers.
The contrast with the US system is significant. While the EU requires manufacturers to demonstrate chemical safety before market access, the US historically has allowed chemicals into commerce and acted only after evidence of harm emerged. The 2016 amendments to TSCA improved EPA’s authority to evaluate and restrict chemicals, but the pace of review remains slow relative to the number of substances in active use. This regulatory patchwork means your exposure to a given chemical can depend heavily on where you live and where the products you buy were manufactured.