What's the Worry With Chemicals?

Alexandra McNair

Chemicals can be dangerous. Chemicals can poison fish, pollute clean and safe drinking water for communities and cause issues to our health.

There are some drastic changes to our scientific understanding of what we knew about the impact that chemicals have on our health. It used to be known that “the dose made the poison.” I recently took a class from two Johns Hopkins professors who taught that we could protect the health of people, if we kept their exposure levels low and below a certain number (permissible exposure limits (PELs) or recommended exposure limit (RELs). Now, we know that it’s not just the dose that matters.

New science and research has taught us that levels which were once thought to be safe at low exposure levels, has the potential to be quite harmful. One example is that there are no safe levels of exposure to lead for children. Small amounts can cause damage to the brain and nervous system. This concept can most certainly be applied to a list of chemicals that fall into the category of endocrine disruptors, also known as hormone disruptors which are frequently used in our dyes and detergents. Not only can it cause lasting harm to the planet, but it creates hormone imbalances that cause tumors to grow inside body tissue.

Other examples of hormone disrupting chemicals are PFC’s and phthalates.

  1. Per-and polyflourinated chemicals (PFC’s): are in our waterproof clothing because they have the ability to repel water. They also have the ability to bio-accumulate in human blood and milk. They have hormone disrupting properties with impact our reproductive systems and immune system as well as potentially carcinogenic in animal tests. According to the EPA’s “Phthalate Action Plan,” for certain pthalates the adverse health effects on the development of the male reproductive system are the most serious.”

  2. Phthalates: Mainly used in plastics, like polyester. These chemicals are commonly found in human tissues, especially in children. DEHP is one of the most widely used and is known to interfere with the reproductive organs of males and females. No legislation exists in most countries.

Endocrine disrupting chemicals are of special concern to children and the effects on early development children below the age of 12 are often irreversible and may not become evident until later in life.

According to ChemHat, new science has also taught that there are many factors that affect how we respond to chemicals. These include dose but also include:

  • Timing of exposure

  • Duration of exposure

  • Previous chemical exposures

  • Age

  • Sex

  • State of health

  • Genetic makeup

  • Individual metabolism

  • Environmental and economic factors

  • Route of exposure

Most occupational health rules were written based on the old understanding that every chemical had a “safe” level of exposure. Now, we ask companies to consider the precautionary principle, meaning that they preventively restrict chemicals, even when there is scientific uncertainty. 

Alexandra McNairComment