The Long-term Effects of Environmental Toxicity

Each year, thousands of new chemicals are introduced into the environment for use in manufacturing, pharmaceuticals, and other industries. In the United States alone, more than 70,000 synthetic chemicals are used commercially, providing significant opportunities for insufficiently tested materials to enter the environment. Though these substances do undergo testing before they are approved for commercial use, these tests rarely look at the long-term or intragenerational effects of their use. When we allow inadequately tested materials do enter the environment, we risk exposing ourselves to potentially toxic substances. In this paper, I argue that the failure to test synthetic chemicals for long-term effects before commercial approval poses a significant risk to humans and other species. I’ll provide several examples of toxic substances that have been used commercially but that can do serious damage to those who are exposed over an extended time.

Lead has been used for centuries in a variety of manufacturing capacities. In North America, lead has been used as a pesticide, as a base for paint, as a soldering substance, and as a compound in gasoline (Moore 2007). Though lead has been recognized as toxic since the early 1900s, the substance was not significantly regulated until the early 1970s with the establishment of the Environmental Protection Agency (EPA) and the passage of the Lead-Based Paint Poisoning Act. In 2008, the restrictions established by the EPA were made more stringent, requiring industries to reduce levels of lead pollution. Lead is an extremely toxic substance, affecting the formation of blood by slowing the maturation of red blood cells and inhibiting the synthesis of hemoglobin (Moore 2007). Exposure to lead may impair fertility, cause spontaneous miscarriages, and cause mental retardation in children. Over the last several decades, scientists have repeatedly reevaluated the levels of exposure to lead that are thought to be harmful. Levels of exposure that were initially thought to be harmless – despite testing – were eventually proven to have dangerous long-term effects.

The use of asbestos became common in the 1850s with the onset of the Industrial Revolution. For over a century, asbestos was used in building materials, textile manufacturing, brake linings, insulation, floor tiles, cement, and potholders. Exposure to asbestos occurs primarily through inhalation, and primarily damages the lungs. Long-term exposure can result in lung cancer, mesothelioma, and a variety of other conditions that affect the ability of the lungs to function at normal capacity (Moore 2007). Though a handful of isolated studies showed asbestos to be toxic in the early 1900s, manufacturing of the substance continued well into the 1970s. By the late 1970s, developed countries began to phase the material out of commercial use. Asbestos is a key example of a toxic substance that has been used in commercial applications despite long-term risks.

Polychlorinated biphenyls (PCBs) have been used in manufacturing throughout much of the 20th century and continue to be used today. Though PCBs are primarily known for their use in plastics, they have been used in the manufacture of transformers, capacitors, hydraulic fluids, solvents, and adhesives (Moore 2007). In the 1960s, studies began to show that PCBs can have toxic effects even at levels thought previously to be harmless (U.S. Department of Health and Human Services 2000). In Japan, PCBs were responsible for the 1968 outbreak of the “Rice Oil” disease, affecting thousands of Japanese civilians. Those affected by PCB exposure developed chloracne, eye discharge, and swelling of the joints. In Taiwan, a similar phenomenon occurred in 1979. Children exposed to PCBs at birth were found to develop teeth, nail, and pigmentation abnormalities. These same children had abnormally low birth rates and developed learning disabilities as they aged (Moore 2007). The industrial use of PCBs is another key example of a toxic substance that, while initially approved for commercial use, has since been found to have negative health effects resulting from long-term exposure.

Though new chemicals undergo testing before they are approved for commercial use, these tests rarely look at the long-term effects of their use. Allowing inadequately tested materials to enter the environment can cause inadvertent exposure to dangerously toxic substances. In this paper, I’ve argued that the failure to test synthetic chemicals for long-term effects before commercial approval poses a significant risk to humans and other species. Though lead has been used for centuries, we only discovered its toxicity within the last 100 years. Asbestos has been widely used in building materials throughout the 20th century but was only phased out of commercial use beginning in the 1970s. PCBs are only recently beginning to be understood as toxic and has not yet been phased out of use in many industries. Each of these substances provides examples of substances that were inadequately tested before being used commercially. To ensure the safety of humans and other species, we must establish more stringent requirements governing the use of new chemicals in manufacturing.

Works Cited

Moore, Gary S. Living With the Earth. Third Edition: Concepts in Environmental Health Science. Boca Raton, FL: Lewis Publishers, 2007. Print.

U.S. Department of Health and Human Services. Toxicological profile for polychlorinated biphenyls (PCBs). Atlanta, GA: Agency for Toxic Substances and Disease Registry, 2000. Print.