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Your Environment. Your Health.

Meta-analysis Tracks Progress of Contaminants of Emerging Concern

Rolf Halden, Ph.D.
Arizona State University
NIEHS Grant R01ES020889

An NIEHS-funded meta-analysis of 143,000 peer-reviewed research papers revealed that the time between when the initial safety concern about a contaminant emerges and when that concern warrants appropriate action is about 14 years. The study’s author says that decreasing both the number of contaminants of emerging concern that enter commerce and the time required to take action is necessary to better protect human health and the environment.

The author examined 30 years of publishing activity for the following 12 contaminants of emerging concern: dichlorodiphenyltrichloroethane (DDT), trichloroacetic acid (TCAA), N-nitrosodimethylamine, methyl tert-butyl ether, trichloroethylene, perchlorate, 1,4-dioxane, prions, triclocarban, triclosan, nanomaterials, and microplastics. Harmful environmental agents showed a common pattern of rising to a level of peak concern over 14 years and then declining to a baseline level. The author reports that contaminants of concern emerge, and some re-emerge, because of improved scientific analysis capabilities; scientific paradigm shifts such as the discovery of infectious proteins; and the development, marketing, and mass consumption of new products such as antimicrobial personal care products, microplastics, and nanomaterials.

Citation: Halden RU. 2014. Epistemology of contaminants of emerging concern and literature meta-analysis. J Hazard Mater; doi: 10.1016/j.jhazmat.2014.08.074.

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