What is chemical pollution

The Impact of Hazardous Chemicals on Population Health: What Is Known and What Can Be Done to Reduce Risk?

1. How are we burdened by harmful chemicals and how can their effects be prevented?

Chemical substances, whether of natural origin or manufactured, are part of our environment.

  • To the natural chemicals include, for example, arsenic and fluoride in drinking water, fine and airborne dust particles as well as sulfur dioxide from volcanic emissions or forest fires or natural toxins;
  • Manufactured chemicals include industrial and agricultural products such as pesticides, petroleum products, processed metals, and combustion products such as toxic gases and particles from industrial emissions and fuel burning. Some chemicals are manufactured for specific uses by everyday products, while others are unwanted by-products, waste or products of combustion.

People can be exposed to these harmful chemicals in a number of ways: through the food we eat, the water we drink, the air we breathe, and our work environment. Monitoring tools are in place for each path to alleviate this burden, and workers can be protected by applying proper safety rules. In many developing countries, however, there is a lack of these regulations and the means to enforce them. For this reason, reducing exposure to harmful chemicals is one of the components of the three sustainable development goals1: SDG 3 "Healthy life for everyone", SDG 12 ("Sustainable Consumption and Production") and SDG 6 "Water and sanitation for everyone".


2. How do harmful chemicals affect public health?

The chemical, physical and toxicological properties of chemicals vary widely. While many of these substances are neither dangerous nor persistent, others can be life-threatening on contact or persist in the environment, accumulate in the food chain, travel long distances from where they are released and be harmful to human health at low concentrations.

Harmful chemicals can thus have a major impact on the health of the population2 to have. Global exposure to disease from environmental pollution and improper handling of harmful chemicals results in at least 4.9 million deaths / year, including at least 1.2 million deaths from industrial and agricultural chemicals; Acute poisoning accounts for 2% of all deaths and 1.7% of the total disease burden worldwide. Heavy metals, pesticides, solvents, paints, cleaning agents, kerosene, carbon monoxide and pharmaceuticals, for example, lead to accidental poisoning, which leads to death in an estimated 193,000 cases each year, the majority of which is due to avoidable pollution.

Exposure to certain toxic chemicals can cause cancer, decreased nervous system development in children, Parkinson's disease, side effects during pregnancy, cataracts, chronic lung disease, and even suicide. Over a third of ischemic heart disease, the leading cause of death and disability worldwide, and over 42% of strokes, the second largest cause of the world's death rate, could be prevented if exposure to harmful chemicals could be reduced or eliminated. For example, secondhand smoke and air pollution contribute to 35% of acute lower and upper respiratory infections, including pneumonia, bronchitis, otitis and bronchiolitis, the leading cause of death in children. These harmful stresses are also associated with low birth weights and miscarriages or stillbirths. The figure below shows the number of deaths and the disability-adjusted years of life (DALY)3which may be due to environmental factors.

Fraction of deaths and DALYs attributable to the environment globally, 2012

2 To better understand the difference between the terms hazard and risk in assessing the properties of a chemical, watch the short animation video: www.youtube.com/watch?v=PZmNZi8bon8 Subtitles are in English, French, Dutch, Spanish, Chinese, Russian, and German; a French version is also available here: https://youtu.be/wRmfvFYDNr8
3 That calculated for a disease or a state of health Disability-adjusted year of life (DALY) is the sum of the years of life lost (YLL) due to premature mortality in the population and the years of life lived with illness / disability (YLD) in people living with the state of health or its consequences. A DALY can be thought of as a lost year of a “healthy” life. (WHO)

3. What can be done in practice to reduce the burden?

The World Health Organization (WHO) estimates that 71% of accidental poisoning could be avoided by increasing chemical safety. Measures to be taken may vary across sectors, but all focus on better regulation of chemicals and contaminants where appropriate. This includes:

  • By reducing or eliminating exposure to chemicals, e.g. B. from pollution of the ambient air, domestic air pollution (especially from coke ovens), from passive smoking and lead, over a third of ischemic heart diseases and around 42% of strokes could be prevented;
  • Smoking bans: In various European and North American countries, reducing exposure to secondhand smoke has a positive impact on health;
  • Further control of industrial emissions in many countries: By changing the way people deal with dust and dusty environments in many countries, and by introducing protective measures on the part of workers, all of the measures have had a positive impact on workers' health;
  • The materials used in the construction industry: Urban planning and water supply management can improve the health of the general population;
  • Transition from current energy sources to healthier forms - Fossil fuels, coal or biomass that are not environmentally sustainable have negative consequences for health.

Social factors also influence the burden and impact of environmental risks and must be systematically included in risk monitoring and strategic planning.

4. What is the financial impact of exposure to harmful chemicals on society?

It is difficult to make a global estimate, but for each sector specific examples can be helpful in understanding the scope of the problem:

  1. In Paraná, Brazil, for every dollar spent on pesticides, approximately $ 1.28 is allocated to medical care and absenteeism due to incapacitation from work-related poisoning;
  2. In Hong Kong, the direct and indirect costs of secondhand smoke are around $ 156 million a year;
  3. In the United States, the cost of treating ischemic heart disease from secondhand smoke is estimated at $ 2 billion to $ 6 billion per year. Smoking bans are very cost-effective measures for public health;
  4. In the European Union, the estimated economic cost of premature death from environmental and household air pollution is around EUR 1.5 trillion.

Overall, avoiding exposure is essentially more cost-effective than treating the diseases that result from it.