Assessing Risks for Inhalation and Ingestion of Pollutants
Pollution or Prevention?
Semipermeable Membranes and Bioaccumulation
Sources of Potential Groundwater Contamination
The East Fork Project
Toxicants and California Blackworms
|A Scientific View of Risk
This background document looks at some everyday risks and compares them with perceived risks of contracting cancer and other diseases through environmental pollution. It also discusses some of the reasons why the general public and risk professionals frequently have differing views on risk.
|An Introduction to Toxicology
The subject of toxicology can be quite complex and a basic understanding of its fundamental principles is important if citizens are to make learned decisions about the risks and choices inherent to environmental health issues.
|Introduction to Groundwater Hydrology
Groundwater hydrology is the study of the occurrence, movement, and quality of underground water. The field is interdisciplinary, drawing on the subjects of physics, geology, chemistry, soil science, and plant physiology.
|Principles of Environmental Site Assessment
Polls show that the public’s top environmental concern is toxic releases from active and abandoned hazardous waste sites. This background discusses some of the scientific factors considered in evaluating the environmental risks posed by these facilities.
|Assessing Risks for Inhalation and Ingestion of Pollutants
This investigation focuses on the basics of human and ecological risk assessment. The activity uses hypothetical scenarios to investigate inhalation of an airborne pollutant and ingestion of a waterborne pollutant. Working in pairs, participants investigate differences in overall exposure to contaminants by calculating inhalation intakes and water ingestion doses that result from varying body weight, years of exposure, inhalation or water ingestion rates, and duration of each exposure event for different hypothetical individuals. By working through these calculations, participants gain an understanding of risk assessment and of what conditions are most vital in reducing exposures to air-and waterborne pollutants. They also gain an awareness of how difficult it is to find clear-cut answers to environmental problems.
In this simulation, participants are “exposed” to various agents (confetti pieces) and then determine their exposure levels. A comparison between naturally occurring and synthetic pesticides is also made. This activity helps participants understand that chemicals may affect different people in different ways. Participants also realize that their perceptions of dangerous materials may not be realistic and that the news media may not provide all of the information needed to make healthy choices.
This activity is an environmental simulation set in the following scenario. A mysterious illness infects more than a dozen people during a summer in Kildare, USA, and the possibility of an epidemic is sending fear throughout the town. To take part in the simulation, the activity participants will play the parts of environmental health investigators to find what is causing the illness, how it is being spread, and what should be done in order to resolve the problem. This simulation incorporates the concepts of bioaccumulation, biomagnification, genetic variability, and metabolism/transformation of a safe substance into a toxin. Participants consider economics and ethics to formulate persuasive arguments to support their actions and decisions.
|Pollution or Prevention?
In this lab, participants perform extractions on a sample to achieve a specified allowable concentration limit. They relate their results to the economics of cleaning up polluted sites.
|Semipermeable Membranes and Bioaccumulation
Organisms can be exposed to environmental toxins through a number of biological pathways, including osmosis and diffusion. This exercise examines basic diffusion and osmosis, along with a model organism’s response to exposure to two simulated environmental toxins.
|Sources of Potential Groundwater Contamination
This activity is about the potential risks to groundwater supplies. You may wish to use it following a “parts per million” activity. Participants construct several models that demonstrate potential sources of contamination, including agricultural fields, oil spills, disposal lagoons, sinkholes, landfills, leaky barrels, and faulty septic systems. Each participant will construct one type of system, answer the assigned questions, and share his or her findings with the other members of the group.
|The East Fork Project
This activity is based on an actual situation in southwestern Ohio. After a discussion on water pollution and environmental health hazards, participants will be asked to identify possible sources of health risks, types of exposures, routes of exposure, and populations that could be affected. Participants will then conduct a mock zoning board meeting to decide what should be done regarding future development in the area. Interested participants could attend an actual Planning Commission meeting and then later present what they learned to the rest of the class.
|Toxicants and California Blackworms
In this investigation, participants work in groups to determine the normal behavior of California blackworms (Lumbriculus variegatus). They then determine how various concentrations of assigned toxicants affect the worms’ behavior. This investigation introduces testing of potential toxicants, an important component in environmental health science.