Environmental chemistry facts for kids

Environmental chemistry is a cool science that looks at what happens with chemicals in nature. It studies how chemicals get into the air, soil, and water, what they do there, and where they end up. It also checks how human activities affect these chemicals and the environment.

This science mixes ideas from different areas like atmospheric chemistry (studying the air), aquatic chemistry (studying water), and soil chemistry. It also uses analytical chemistry to measure things. Environmental chemistry is different from green chemistry, which focuses on preventing pollution from the start.

To understand environmental chemistry, scientists first learn how a clean, natural environment works. They find out which chemicals are naturally present and how much of them there are. Then, they study how humans change the environment by adding new chemicals or too much of existing ones. Environmental chemists use many ideas from chemistry, like understanding chemical reactions, how things dissolve, and how to measure tiny amounts of chemicals.

What is Contamination?

A contaminant is a substance found in nature at levels higher than normal, or a substance that shouldn't be there at all. Often, this happens because of human activities. The word "contaminant" is sometimes used like "pollutant". A pollutant is a substance that causes harm to the environment around it.

Sometimes, a contaminant might not seem harmful at first. But later, it can become clear that it has bad or toxic effects. The place or living thing affected by a pollutant or contaminant is called a receptor. For example, the soil or a fish could be a receptor. A sink is a place or chemical that holds onto the pollutant and interacts with it.

How We Measure Environmental Health

Scientists use chemical measurements to check the health of our water. Some important things they measure include:

• Dissolved oxygen (DO): How much oxygen is in the water. Fish and other aquatic life need this to breathe.
• Chemical oxygen demand (COD) and biochemical oxygen demand (BOD): These tell us how much pollution is in the water that uses up oxygen.
• Total dissolved solids (TDS): The total amount of all dissolved stuff in the water.
• pH: How acidic or basic the water is.
• Nutrients: Like nitrates and phosphorus, which can come from fertilizers and cause problems if there's too much.
• Heavy metals: Such as copper, zinc, cadmium, lead, and mercury, which can be very harmful.
• Pesticides: Chemicals used to kill pests, which can wash into water.

Real-World Uses of Environmental Chemistry

Environmental chemistry helps different groups and agencies around the world. They use it to find out what pollutants are present, where they come from, and what they are. For example, organizations like the Environment Agency in England and Wales, and the United States Environmental Protection Agency in the US, use it for many things:

• Heavy metal pollution: Finding out when industries pollute land with heavy metals. These metals can then move into water and be taken up by plants and animals.
• Nutrient pollution: Tracking how nutrients from farms wash into rivers and lakes. Too many nutrients can cause algal blooms, which are huge growths of algae that harm water quality and aquatic life (this is called eutrophication).
• Urban runoff: Studying pollutants that wash off city surfaces like roads and parking lots when it rains. These can include gasoline, motor oil, other hydrocarbons, metals, nutrients, and sediment (soil).
• Organometallic compounds: Investigating chemicals that contain both metal and carbon atoms, which can sometimes be toxic.

How Environmental Chemists Study Chemicals

Measuring chemicals accurately is a very important part of environmental chemistry. It gives scientists the information they need for their studies.

Scientists use many different ways to measure chemicals. Some older methods include gravimetric analysis (measuring weight) and titration (measuring how much of one chemical is needed to react with another).

For tiny amounts of metals or organic compounds, they use more advanced tools. Metals are often measured using special machines like Atomic Absorption Spectrophotometry (AAS) or Inductively Coupled Plasma Mass Spectrometry (ICP-MS). These machines can detect very small amounts of metals.

Organic compounds are often measured using methods like gas chromatography–mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC/MS). These techniques separate different chemicals and then identify them.

Environmental chemists also measure radiochemicals. These are pollutants that give off radioactive materials, like alpha and beta particles. These can be dangerous to people and the environment. Special counters, like particle counters, are used to measure them. Scientists also use bioassays to see how chemicals affect living things.

Other pages

• Chemists Celebrate Earth Day
• Environmental monitoring
• Freshwater environmental quality parameters
• Green chemistry
• Green Chemistry Journal
• Journal of Environmental Monitoring
• Important publications in Environmental chemistry
• List of chemical analysis methods

Images for kids

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  White bags filled with contaminated stones line the shore near an industrial oil spill in Raahe, Finland

See also

In Spanish: Química ambiental para niños