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If Canadian laws and regulations to protect the environment and public health were indeed protecting public health, we would expect declining diseases associated with anthropogenic exposures, rather than the opposite.
Yes, today children are on average exposed to lower levels of tobacco smoke, some old pesticides, and lead in drinking water, gasoline exhaust and paint chips/dust. Indeed, lower tobacco and lead levels are seen in Canadian biomonitoring studies; pesticides are less frequently quantified.
Measures against tobacco, lead and selection of pesticides have not, however, prevented endocrine-related obesity and metabolic syndrome, disorders of early development and sexual differentiation, and cancers in hormone-sensitive tissues (e.g., breast, prostate, thyroid). This is as chemicals called “endocrine disruptors”—groups of chemicals known to mimic hormones and/or interfere with endocrine signalling (e.g., phthalates, bisphenols, flame retardants and some pesticides)—remain in commerce. For decades they contaminate in water, food and products, in homes, schools and the workplace, and in the environment, before being restricted or banned.
Endocrine disruption does not follow a classic dose-response, and can be perpetuated under risk-based management, as practised in North America.
Endocrine disrupting chemicals (EDCs) require actions based on their innate hazard. With many thousands of EDCs, classes of similar chemicals require group actions.
Single-chemical regulation does not work, and Canadian-led research highlights how aggregate effects of low dose mixtures of chemicals can cause cancer.1 This explains today’s increasing health conditions associated with altered signalling in hormone-driven endocrine systems. Examples include: disorders of sexual development and reproduction; obesity, metabolism and diabetes; neurological development and function; and some cancers. As well, intergenerational effects occur even when the genetic code is not mutated; rather, epigenetic changes that affect expression and suppression of particular genes, can alter susceptibility to dysfunction and disease. Higher prevalence is seen in racialized2 and more highly exposed populations.
Examples of adverse trends in public health linked to toxicants include:
As federal laws such as the Canadian Environmental Protection Act (CEPA), the Pest Control Products Act (PCPA), and their regulations and administration are studied and reformed, the are opportunities to counter climate chaos, biodiversity declines, chronic diseases and cancer. These include
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