To assess the impacts of various risk management measures that have been implemented globally, the Food and Agriculture Organization of the United Nations (FAO) compiled a report on the exposure of humans and food-producing animals to important endocrine-disrupting chemicals (EDCs) over a 20-year period.

Given the many changes in the manufacture, use, and control of significant EDCs in the past two decades, the report examined trends in the exposure of human populations and food-producing animals to certain chemicals from 2004–2024. Although FAO is primarily concerned with dietary exposure to EDCs, most of the available information on exposure trends is from human biomonitoring, which does not distinguish between routes of exposure. FAO’s report focused on chemicals included in the Stockholm Convention on Persistent Organic Pollutants (POPs), which has been the source of much of the available information on human exposures; there is a considerable overlap among chemicals considered to be EDCs and chemicals classified as persistent organic pollutants.

Overall, the report noted a downward trend in exposure to EDCs for which there have been specific regulatory controls placed on their manufacture and use, for which public health concerns have led to voluntary control measures by the manufacture or use industries, or for which publicly available information has raised concerns in the general population. However, exposure to EDCs have not been eliminated due to the incomplete application of control measures and the chemicals’ environmental persistence, and exposure trends vary for different EDCs:

• Organochlorine pesticides (OCPs): The manufacture and use of many organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane (DDT), ceased in the 1980s, and therefore, evidence shows exposure to organochlorine compounds to be continuously decreasing. Additionally, exposure to polychlorinated dibenzo dioxins/furans (PCDD/F) and dioxin-like polychlorinated biphenyls (DL-PCBs) have similarly declined over the 20-year period, except for in northern China, where inexplicable increasing exposure was observed in the late 2000s/early 2010s.
• Polybrominated diphenyl ethers (PBDEs): Trends in concentrations of PBDEs are complicated by the existence of multiple industrial formulations and mixed voluntary industry control measures and regulatory measures. For example, penta- and octa-brominated diphenyl ethers (BDEs) were phased out earlier than other PBDEs, and therefore, uniform decreases in BDE-47, -99, and -100 have been observed. At the same time, decreases in BDE-153, BDE -209, and hexabromocyclododecanes (HBCDDs) have only been noted in more recent studies. BDE -209 was still in use longer than other penta- and octa-BDE formulations, and HBCDDs are still currently used in some regions.
• Phthalates: In general, the evidence shows a decrease in human exposure to low-molecular weight phthalates over the 20-year period, which became more apparent after regulatory action was taken in Europe in 2013. There is less evidence of decreases in exposure to high-molecular weight phthalates, which were not included in the European regulatory action. Additionally, several studies have shown that human exposure to phthalate substitutes, such as di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH), are increasing.
• Bisphenols: Decreases in exposure to bisphenol A (BPA) appear to have occurred earlier in Asia than in Europe and North America. While most studies have demonstrated decreases in BPA exposure, the decreases are often not substantial. Additionally, despite some evidence showing substitution of BPA by other bisphenols to some extent, no sustained trends in exposure to other bisphenols was apparent in the literature.
• Parabens, triclosan, and benzophenone: Although the use of these chemicals are regulated in some countries, they have not been banned, and decreases seen in exposure to parabens and triclosan are likely due to manufacturers’ responses to public pressure. There is moderately consistent evidence for decreasing exposure to parabens and triclosan, particularly for methylparaben and propylparaben. Increases have been seen in exposure to benzophenone-3 (BP-3), a sunscreen ingredient.
• Alkyl phenols: Only two studies were identified that considered trends in human exposure to alkyl phenols. The two studies, one in Germany and one in Japan, indicated decreases in human exposure to alkyl phenols after 2012.
• Per- and polyfluoroalkyl substances (PFAS): Human exposure to shorter-chain PFAS appears to have decreased between 2000 and 2008, with the peak of exposure varying between countries. There is limited evidence for decreased exposure to longer-chain PFAS, with some indications of increases in exposure. Additionally, here are relatively few studies on trends in the PFAS exposure of food-producing animals, and the available studies give inconsistent indications of whether exposure is increasing or decreasing.
• Phytoestrogens: Only two sources of information were found on trends in exposure to phytoestrogens, particularly the soy isoflavones, daidzein and genistein. There is little evidence of a trend in exposure to these chemicals. Data from the U.S. National Health and Nutrition Examination Survey (NHANES) are suggestive of increased exposure to daidzein, possibly attributable to the increased use of soy products in processed foods.