Effects vary based on the contaminant.
Algal Blooms- Mild symptoms can include stomach pain, rash, headache, coughing, watery eyes, nose irritation, or sore throat. More advanced symptoms may present as seizures, liver damage, and/or irregular heartbeat.
Chemicals- Chronic exposure to uranium in drinking water has been linked to renal dysfunction, kidney failure, and kidney cancer in adults. Breathing radon gas released from water or from the contamination of indoor air can cause lung cancer in adults, especially in tobacco smokers. Chronic exposure to water contaminated by elevated levels of arsenic has been associated with miscarriage in pregnancy, skin lesions, neuropathy and cognitive declines, diabetes, stroke, peripheral vascular disease, and cancer. Manganese poses neurological risks; in chronic exposures, Parkinsonian-like symptoms and other neurological deficits may develop.
Bacteria- such as Eschericia coli and viruses such as Vibrio cholerae cause severe gastrointestinal symptoms including nausea and vomiting, anorexia, severe watery diarrhea, and dehydration.
Lead- Children may present with nonspecific symptoms that progress with increasing blood lead levels (BLL). Symptoms may include headaches, abdominal pain, loss of appetite or constipation, signs of clumsiness, agitation, or decreased activity and drowsiness, vomiting, stupor, and convulsions. Subtle symptoms, such as irritability, disrupted sleep, anorexia or abdominal discomfort, may occur in some children even at relatively low BLLs. For more information on lead, visit our Lead for Health Professionals page.
Perfluoroalkyl Substances (PFAS) – PFAS are not metabolized but bind to serum proteins and accumulate in the serum, liver and kidney. They are excreted mainly in urine but also feces. Not all health effects of PFAS are known, but effects on multiple body systems have been described. PFAS exposure is associated with increases in cholesterol levels, decreases in birth weight, lower antibody response to vaccines, kidney and testicular cancer, pregnancy-induced hypertension, preeclampsia, and changes in liver enzymes. Read more here about PFAS from the Agency of Toxic Substances and Disease Registry.