Pollutants in groundwater have become more of a point of public concern in recent years, and that concern is growing all the time. Polluted groundwater affects fish and local wildlife populations, and also has the potential to filter through into the human diet via freshwater fish and drinking water. Below are details of some common pollutants that affect groundwater, as a simple list of the nitrates, phosphates and detergents that make up the bulk of pollutants might not make a huge amount of sense to the average reader.
According to Soil Facts, common groundwater pollutants can be either organic or inorganic compounds. The organic chemicals polluting groundwater tend to be cabon or nitrogen-based, with additional amounts of sulphur, phosphorous, nitrogen and chlorine. Organic pollutants tend to include chemicals such as solvents, pesticides, petroleum-based chemicals, pesticides and other industrial by-products.
On the inorganic side, many groundwater pollutants tend to include nitrates, chlorides and heavy metals. The nitrates tend to come from fertilizers used in agriculture, decayed organic matter or animal manure, while the heavy metals such as copper and lead are almost always a result of industrial activity.
Organic pollutants affecting groundwater are generally present in only trace amounts, a few parts per billion or even parts per trillion, and so their effect on humans is hard to judge, even when drinking water is contaminated. Even so, the utmost care is taken in trying to filter as many organic pollutants out of drinking water as possible.
Inorganic pollutants such as nitrates are more of a concern. Although adults can absorb and process a large amount of nitrates ingested via food and water, those under six months old are at risk from nitrate consumption due to their under-developed digestive tracts, which contain bacteria capable of turning relatively harmless nitrate into toxic nitrite. Once introduced into the bloodstream, nitrite reacts with blood in order to create methemoglobin, a compound which hampers the blood's ability to carry oxygen around the body.
This situation can lead to methemoglobinetnia, and infants may show signs of suffocation as the oxygen levels in their blood decrease. The most obvious symptom is bluish skin around the eyes and mouth. Luckily, this condition is very treatable.
Livestock can also be affected by nitrate pollutants of groundwater when the polluted water is added to foods which already have a high concentration of nitrates. Horses are particularly prone to nitrite poisoning, as are cattle and sheep and other grazing lifestock to a lesser extent, as nitrates become concentrated in their grazing food.
These common pollutants that affect groundwater are monitored closely, and efforts are made to ensure as little as possible enters human bodies via livestock or drinking water, but nitrate pollution is a key cause for concern among environmental groups.