Arsenic pollution: what are the dangers for humans and the environment?

Like cadmium, arsenic does not disappear naturally. It remains present in soils and groundwater for centuries.

Concerning characteristics

• Solubility : Inorganic arsenic can easily dissolve in water, contaminating drinking water.

• Mobility : it moves through the environment, affecting vast geographical areas.

• Bioaccumulation : it accumulates in living organisms, particularly fish and crustaceans.

Arsenic pollution is particularly difficult to control because it is both natural and anthropogenic.

1. Metallurgical industries : zinc extraction and refining, galvanizing, welding, manufacturing of rechargeable nickel-cadmium batteries.

2. Phosphate fertilizers : often contaminated with cadmium as an impurity.

3. Combustion of fossil fuels : atmospheric emissions which then fall back onto the ground.

4. Electronic and plastic waste : increased pollution due to poor management of recycling channels.

5. Colored pigments and plastics : historical use of cadmium compounds for paints and polymers.

Arsenic enters the body mainly through drinking water and food (rice, vegetables, seafood).

• Cancers : Arsenic is classified as a known carcinogen (Group 1, IARC) . It is associated with cancers of the skin, liver, bladder, and lungs.

• Cardiovascular system : hypertension, heart disease.

• Skin : hyperpigmentation, skin lesions, keratoses.

• Nervous system : neurological disorders, memory loss, developmental delay in children.

• Kidneys and liver : chronic long-term damage.

Long-term exposure to arsenic can be fatal, even with repeated low doses.

Arsenic enters the body mainly through drinking water and food (rice, vegetables, seafood).

Documented toxic effects

• Cancers : Arsenic is classified as a known carcinogen (Group 1, IARC) . It is associated with cancers of the skin, liver, bladder, and lungs.

• Cardiovascular system : hypertension, heart disease.

• Skin : hyperpigmentation, skin lesions, keratoses.

• Nervous system : neurological disorders, memory loss, developmental delay in children.

• Kidneys and liver : chronic long-term damage.

Long-term exposure to arsenic can be fatal, even with repeated low doses.

Arsenic pollution also directly affects the environment:

• Soil : lasting contamination, rendering agricultural land unsuitable for certain crops.

• Water : pollution of groundwater and rivers, making the water unfit for consumption.

• Aquatic fauna : bioaccumulation in fish and crustaceans, which become unfit for human consumption.

• Food chain : gradual transfer of pollutants to higher predators, including humans.

To limit the risks associated with arsenic pollution, several international regulations impose maximum thresholds:

• WHO (World Health Organization) : limit set at 10 µg/L of arsenic in drinking water.

• European Union : same threshold as the WHO, as stated in the European directive on drinking water.

• Food products : specific thresholds for rice and rice-based products, which are particularly monitored.

Despite these rules, millions of people around the world still consume water beyond these thresholds.

Arsenic pollution is closely linked to other heavy metals, which exacerbate the overall impact on health and the environment.

The list of heavy metals underlines the need for comprehensive pollution management to limit their cumulative effects.

Good agricultural practices

• Use varieties of rice and crops that are less absorbent of arsenic.

• Control the origin of irrigation water.

• Improve soil drainage to limit arsenic mobility.

Water treatment

• Activated carbon or biochar-based filters .

• Membrane processes (reverse osmosis, nanofiltration).

• Specific adsorbents : iron oxides, zeolites, bio-materials.

Industrial and regulatory measures

• Ban on arsenical pesticides.

• Strict monitoring of industrial discharges.

• Gradual decontamination of polluted mining sites.

For individuals

• Check the quality of your drinking water (especially in at-risk areas).

• Diversify your diet to limit exposure.

• Avoid CCA-treated wood for domestic construction.