but can progress to chemical lung damage, pulmonary edema, and even death. PCBs – People exposed to high levels of PCBs can exhibit skin conditions, such as rashes and liver damage. Common symptoms include dermal and ocular lesions, irregular menstrual cycles and lowered immune responses. Other symptoms include fatigue, headaches, coughs, and unusual skin sores. PAHs – The U.S. Environmental Protection Agency (EPA) classified seven PAH compounds as probable human carcinogens: benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, dibenz(a,h)anthracene, and indeno(1,2,3-cd)pyrene. Pathogens Pathogens are bacteria and viruses that can be found in water and cause diseases in humans. Pathogens found in contaminated runoff may include: Cryptosporidium parvum – Primary symptoms of C. parvum infection are diarrhoea. Other symptoms can include anorexia, nausea/vomiting and abdominal pain. Giardia lamblia – Symptoms of infection include diarrhea, malaise, excessive gas, steatorrhoea, epigastric pain, bloating, nausea, vomiting, diminished interest in food, and weight loss. Salmonella – Symptoms are usually gastrointestinal. This can include nausea, vomiting, abdominal cramps and bloody diarrhea with mucus, headache, and fatigue. Parasitic worms (helminths) – Conditions associated with intestinal helminth infection include intestinal obstruction, insomnia, vomiting, weakness, and stomach pains. Environment The environment is impacted by nonpoint source pollution through the input of sediment and nutrients from multiple sources directly into the water system. Toxic contaminants and chemicals Toxic chemicals and contaminants, like motor oil, fuel, and industrial facility waste can enter the water system by storm water runoff. These chemicals, many of which can contain heavy metals, can enter the water system and coat the species present in the water. This can lead to death of the aquatic organisms which can cause increases in the amount of nutrients in the system from the decaying animals. Sediment Sediment or suspended sediment in the water is soil that would not normally be present in the water column. When the sediment is suspended up in the water column, it blocks out the sunlight which is needed by bottom dwelling plants. If these plants, called submerged aquatic vegetation, are deprived of sunlight for a significant amount of time, they will die. These plants are a significant source of food for many aquatic organisms as well as trap oxygen and sediment. When there is an excess of dying plants in an aquatic ecosystem, it can lead to eutophic or hypoxic conditions in the water body. Nutrients The primary nutrients found in water due to nonpoint source pollution