Environmental Toxins

What are Toxicants and Toxins?

There are two different concepts about compounds that produce adverse health effects: Toxicants and Toxins. Both can cause biochemical harm differently.


Toxicants (toxic chemicals) are man-made products, artificial products introduced into the environment due to human activity. Examples are industrial waste products and pesticides, carcinogens like asbestos, VOCs like benzene, etc. At PCS, we deal mainly with toxicants that are environmental pollutants.


Toxins are natural products such as the ones found in poisonous mushrooms or in a snake's venom. They are poisons produced within living cells or organs of plants, animals, and bacteria. Toxins like hemotoxins in snakes destroy red blood cells. Necrotoxins like those produced in bacteria destroy cells in tissues.

Are children more susceptible to toxicants than adults?

Since children eat more food, drink more water, and breathe more per pound than adults, they intake more toxicants into their bodies. Besides, their metabolism and defense systems are not well developed which increase susceptibility to chemical exposures. Children's bodies are growing and developing more rapidly so, chemicals that can harm development can do maximum damage at this critical time.  

Children are exposed to toxicants as early as conception and therefore the in-utero development may be affected by compounds that enter the mother's body by inhalation or ingestion as well as dermal contact. Parents of infants and toddlers are challenged by the child constantly putting their hands (and other objects) into their mouths. This creates a concern of ingesting some toxicants such as pesticides and heavy metals, as well as allergens and dust particulates. The small stature of children also exposes them to volatiles that are low lying or emitted from carpet or other flooring, as well as those encapsulated in dust. 

Where do the toxicants come from?

There are a variety of chemical contaminants found in a variety of sources. These could be of natural origin or resulting from human activity (anthropogenic). The primary source of anthropogenic compounds is the chemical industry (industrial solvents, paints, adhesives, oil and petrochemical industries, household products, pesticides and fertilizers, fabric materials & furnishings, etc.). Regarding chemicals of natural origin, a good example are heavy metals that are present in the environment (mercury, lead, etc.) apart from being the result of human activity.

The list of toxicants that produce adverse health effects is long. However, the following list shows some of the riskiest ones:

  • Polychlorinated biphenyls (PCBs)
  • Pesticides
  • Diesel Particulate
  • Dioxins
  • Volatile Organic Compounds (VOCs)
  • Styrene
  • Trichlorethylene
  • 1,3 butadiene
  • Methyl-tert-butyl ether (MTBE)
  • Benzene
  • Chlorinated hydrocarbons such as Chloroform
  • Heavy Metals
  • Chlorine
  • Phthalates
  • Asbestos
  • Carbon Monoxide, Carbon Dioxide, Nitrogen Oxides, Sulfur Dioxides and Toxins such as fungal, mold and bacteria.

PCS Chemical Fact Sheets:

PCS Chemical Fact Sheets provide a summary of the properties on selected chemicals. They cover basic information that is accessible to everyone. In the present case, the Fact Sheets approach chemical identity, where the compounds come from, how we might be exposed to that compound, potential health effects (signs and symptoms associated with exposures), how we can reduce the exposure to that compound. The basic information allows communities to be aware of the consequences of the exposure to those chemicals (VOCs, PM, Benzene, Nickel, Mercury, Formaldehyde, Silica, Chromium, and Carbon dioxide), which are very common as environmental pollutants.

In the case of Occupational exposure, the PCS Fact Sheets have more detailed information. They are very useful to comply with the "Right to know principle", providing workers with information and training that ensures their awareness of the chemical hazards used in their work area.

Particulate Matter (PM)
Volatile Organic Compounds (VOCs)
Chromium (Cr)
Silica (SiO2)
Mercury (Hg)
Nickel (Ni)
Carbon Dioxide (CO2)