What are the Sources of Environmental Pollution?

The most common sources of pollution are either naturally occurring or human-made. This can be anything from chemical spills from factories to the large amounts of emissions that come from vehicles every day.

It’s important to learn about the different types of pollution and what causes them so you can do your part in preventing and reducing the effects of pollution on our planet.

Sources of Environmental Pollution

Pollution is often described as a point source or diffuse (or non-point) pollution. Point source pollution comes from a single, identifiable source, such as an outfall pipe at a factory. The pollution can be controlled at the source by installing an isolation valve and connecting it to a tank for storage until it can be disposed of properly. Diffuse pollution comes from multiple sources and occurs across a broad area: for example, stormwater runoff carrying fertilizers from agricultural fields.

(i) Point source pollution:

Point source pollution is a pollution source that comes from a single, identifiable point. This is in contrast to non-point source pollution, which results from numerous sources and cannot be traced back to a specific, localized cause. Point source pollution can be controlled through the use of waste treatment plants or similar methods.

Point source pollution includes discharges from pipes, sewers, or other containers that are controlled by an individual or organization. It comes from a specific location and can usually be identified by its source. A common type of point source pollution is human sewer discharge. Other examples include industrial waste discharges, such as when a factory dumps waste products into nearby water bodies such as rivers and lakes; agricultural runoff; and contaminated groundwater discharged via leaching pits or leaking septic systems.

Pollution of this type can be controlled through the use of sewage treatment facilities for domestic sewage and by regulatory enforcement of industrial practices for industrial wastes. The Environmental Protection Agency (EPA) enforces laws against pollution in most countries with developed legal systems and can levy fines against companies that violate these laws. The agency also provides funding to help communities set up facilities to handle point source pollution, especially in small communities where it may not be economically feasible to do so without aid.

(ii) Non-point pollution:

Nonpoint pollution is described as pollution that comes from numerous sources. It is caused by human activities, but not from a single location. The impact of nonpoint source pollution depends on the amount of damaged area and how receiving water is used. For example, if a farmer were to spill fertilizer into a stream, it would be considered a point source of pollution. However, if the fertilizer were to seep through the soil and run off into the same stream during a rain event, it would then be considered nonpoint source pollution.

Nonpoint source pollution can occur from over fertilizing lawns, not properly maintaining septic systems, and improper disposal of pet waste among other things.

The biggest contributor of nonpoint source pollution in the United States is sediment which is mainly caused by agricultural practices. Other contributors include nutrients (fertilizers), pathogens, toxic substances, and debris such as plastics and rubber tires.

Examples of
sources of pollution
Point source or diffusePotential pollutant
Effluent discharges from sewage treatment worksPoint sourceNitrogen (N) and Phosphorus (P), persistent organic pollutants, pathogens, litter, oxygen-depleting substances, suspended solids, and settleable solids
Industrial effluent dischargesPoint sourceN, oxygen-depleting substances and a broad spectrum of chemicals, suspended solids, etc.
Industrial processesPoint sourceBroad-spectrum of chemicals released into air and water
Oil storage facilitiesPoint sourceHydrocarbons
Urban stormwater dischargesPoint source – arising from stormwater runoff (from paved areas and roofs in towns and cities) entering the sewer networkN, P, oxygen-depleting substances, heavy metals, hydrocarbons, pathogens, persistent organic pollutants, suspended solids, settleable solids, litter
Landfill sitesPoint sourceN, ammonia, oxygen-depleting substances, a broad spectrum of chemicals
Fish farmingPoint sourceN, P, oxygen-depleting substances, pathogens, suspended and settleable solids
Pesticide useDiffuseBroad-spectrum of chemicals
Organic waste recycling to landDiffuseN, P, pathogens
Agricultural fertilizersDiffuseN, P
Soil cultivationDiffuseSoil, N, P
Power generation facilitiesDiffuseN, sulfur, mercury, POPs, temperature (thermal) pollution
Farm wastes and silagePoint/DiffuseN, P, oxygen-depleting substances, pathogens, suspended and settleable solids
Contaminated landPoint/DiffuseHydrocarbons, organic chemicals, heavy metals, oxygen-depleting substances
MiningPoint/DiffuseHeavy metals, acid mine drainage, suspended and settleable solids
Leaking pipelinesPoint/DiffuseOil, sewage, hydrocarbons
Domestic plumbing misconnectionsPoint source – connection of domestic appliances and toilets to rainwater drainsP, oxygen-depleting substances, pathogens, suspended and settleable solids, N