Environmental Health and Toxicology

Dr Dubravka Selenic Medical Officer WHO Thailand

Outline

 Environmental Health  Environmental toxins and public health  Sources and types of toxic agents  Mechanisms of toxicology  Environmental health problems  Regional overview of chemical safety in WHO South-East Asia Region

2 | Chemicals burden of disease |

30 April 2020

Environmental Health

 The World Health Organization defines health as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity  Environmental health addresses all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviors. It is targeted towards preventing disease and creating health-supportive environments.  The WHO estimates that 24 % of all global disease burden and 23% of premature mortality are due to environmental factors.

3 | Chemicals burden of disease |

30 April 2020

Potentially harmful chemicals found in many homes

4 | Chemicals burden of disease |

30 April 2020

Significance of environmental toxins

 First widely recognized in 1960’s with DDT and radiation effects from atom bombs  Increasing use of synthetic chemicals in last decades raised concerns  Revelation of toxic hazards in occupation, ambient pollution, waste disposal and consumer products

5 | Chemicals burden of disease |

30 April 2020

Major sources of environmental risk

Toxins Pollution Infectious agents Trauma Radiation Noise Accidents 6 | Chemicals burden of disease |

30 April 2020

Sources of exposure

 Occupation  Ambient pollutants  Point sources-hazardous wastes  Household chemicals  Pesticide residues  Drugs  Lifestyle

7 | Chemicals burden of disease |

30 April 2020

How do toxics affect us?



Allergens

Formaldehyde is a good example of a widely used chemical that is a powerful sensitizer of the immune system. It is directly allergenic and can trigger reaction to other substances .



Sick building syndrome:

headaches, allergies, and chronic fatigue caused by poorly vented indoor air contaminated by various contaminants 

Neurotoxins-

metabolic poison that attack nerve cells(Pesticides acute effect in agricultural workers, lead impaired neurological development in young children)

8 | Chemicals burden of disease |

30 April 2020

Carcinogens

 Carcinogens are some chemicals, air pollution, types of radiation, or certain viruses that can cause or promote cancer.

 About 50 recognized chemicals in environment can cause cancer  Currently, 7.6 million people die from cancer worldwide every year

9 | Chemicals burden of disease |

30 April 2020

Other toxic

substances



Teratogens

- cause birth defects during pregnancy.



Mutagens

- damage or alter DNA in cells (radiation, chemical) “Thalidomide baby”-Butch Lumpkin learned to overcome his deformed arms and fingers to become a professional tennis instructor.

10 | Chemicals burden of disease |

30 April 2020

Reproductive and Children ’s Health

 Environment has shown to impact reproductive health, some examples are elevated rates of cancer in reproductive organs, premature births, miscarriages and birth impairments  Sperm and eggs can be damaged by pesticides, chemicals, or other chemical exposures leading potentially affecting the embryo ’s development  In 2010, the US President ’s Cancer Panel warned that 300 contaminants were found in umbilical cords blood and they said that babies are being born “pre-polluted”

11 |

Endocrine Disrupting Chemicals EDCs

 Endocrine disorders an emerging problem interference with normal functions of the endocrine system  Found in pesticides, bisphenol A (a chemical used to make plastic), some cosmetics, flame retardants, glues, sealants, and cleaning products  Bioaccumulant- accumulate in animal fat and animal products and are then consumed.

12 | Chemicals burden of disease |

30 April 2020

Problems in Environmental Health

 Environmental health is a multisectoral problem, which requires coordination and cooperation among the many different sectors  Health and environmental issues are separated in some developing countries  Lack of data  Environmental diseases mimic other diseases ( multiple causes of disease, fail to detect environmental contribution)  Variation in human sensivity

13 | Chemicals burden of disease |

30 April 2020

Unique Problems in Environmental Health

 Low frequency-High impact – – Cancer Neurological diseases – Reproductive disorders  High Frequency-Low impact – – Skin rashes Acute respiratory distress – Headaches  Adversarial culture –Economic stakes

14 | Chemicals burden of disease |

30 April 2020

Information sources



WHO Environmental Health

http://www.who.int/topics/environmental_health/en/  Health and Environment Linkages Initiative (HELI), WHO and UNEP 

Principles of Environmental Science Companion Site

, William P. Cunningham, University of Minnesota Mary Ann Cunningham, Vassar College  TOXNET http://sis.nlm.nih.gov/enviro.html

 Agency for Toxic Substances and Disease Registry

15 | Chemicals burden of disease |

30 April 2020

Regional overview of chemical safety in WHO South-East Asia Region

Ms Lesley Onyon Regional Advisor Occupational Health & Chemical Safety

Outline

 Briefly review what we known of the burden of disease due to chemicals – BoD  Briefly review what we know about progress of implementation of chemical safety measures in the region  Draw some overall conclusions about chemical safety in the region

17 | Chemicals burden of disease |

30 April 2020

WHO South-East Asian Region



11 Member States: Bangladesh, Bhutan, DPR Korea, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka, Thailand, Timor-Leste

18 | Chemicals burden of disease |

30 April 2020

Human exposure can occur at any stage in a chemicals ’ life-cycle

Water and food safety

Naturally occurring contaminants

e.g. arsenic and fluoride in water

Human exposure

Transport and health, air quality

Combustion products

e.g. air pollutants

19 | Legend:

Chemicals Exposure

Chemicals burden of disease |

Policies and programmes 30 April 2020

Raw materials

e.g. fossil fuels, raw chemicals

Manufacture and transport Manufactured products

e.g. industrial chemicals

Use and disposal Waste and by products

e.g. e-waste, POPs Processes Environmental exposure Chemical safety Occupational, transport and chemical safety Chemical and product safety Occupational, chemical, food & water safety Waste management, chemical, food & water safety Occupational exposure

Estimates of the known burden of disease due to chemical exposure

Knowns and unknowns on burden of disease due to chemicals: a systematic review Environmental Health 2011, 10:9, Published: 21 January 2011 http://www.ehjournal.net/content/10/1/9  Globally - 8.3% of total deaths (4.9M ) & 5.7 % DALYS attributable to environmental exposure & improper management of specific chemicals  2.0% of deaths (1.7% DALYS) from industrial and agricultural chemicals and accidental poisonings

20 | Chemicals burden of disease |

30 April 2020

Current BoD estimates primarily are made from 10 chemicals of major health concern 21 | Chemicals burden of disease |

30 April 2020

Chemicals can move via many pathways

22 | Chemicals burden of disease |

30 April 2020

The tip of the iceberg

 Burden from most chemicals has not yet been assessed – recent estimates are underestimates.

 Continued need for risk assessment and surveillance to strengthen the evidence.

23 | Chemicals burden of disease |

30 April 2020

More frequent outcomes

24 |

Less frequent outcomes

Acute poisonings Diseases caused by high level chronic exposures at work

Occurrence and detection of health impacts from chemicals

Diseases in the general population caused by lower level chronic exposures

Adverse health effects (developmental effects, organ function impairment)

Physiological changes of uncertain significance, body burden

Manifest health effects Health effects only observable in specific surveys or investigations

Adapted from de Hollander et al.

Fraction of disease outcomes traced back to chemicals Fraction of outcomes with often "unknown" aetiology

Need for sound chemicals management

 Production of chemicals continue to grow worldwide – nine-fold increase  Production increased much faster in developing countries  Developing countries increase from 17% (1970) to 31% (2020)  Older and bulk-type chemicals in developing countries ‘specialized’ chemicals in developed countries  Use/import of chemicals increase with development & urbanization

25 | Chemicals burden of disease |

30 April 2020

What do we know in South-East Asian region

 Self-inflicted injuries with pesticides, indoor air pollution, lead poisoning & arsenic poisoning from SEA are very significant (50%). Continued & increasing use of asbestos.

 Environmental contamination from poorly controlled industrial processes - legacy pollution and artisanal/informal industries and “niche” industries.

 Significant challenges with water quality & sanitation & waste management. Country-specific issues, e.g. Chronic Kidney Disease in Sri Lanka ,endosulphan poisoning in India, Arsenic in Thailand  For SEA Non-communicable diseases are the leading cause of death responsible for 80% of all deaths . 19% of all cancers can be attributed to the environment

26 | Chemicals burden of disease |

30 April 2020

DALYs from lead exposure in SEA

27 | Chemicals burden of disease |

30 April 2020

What actions are being taken by SEA Member States

 Nomination of chemical focal points  Implementation of chemical multi-lateral instruments  Implementation of the International Health Regulations  Capacity-building initiatives

28 | Chemicals burden of disease |

30 April 2020

Network of focal points exists already in SEA for chemical safety

 Ministries of Health (8) – Bhutan, DPR Korea, India, Indonesia, Sri Lanka, Thailand, DPRK & Timor Leste  WHO Country Office environmental health focal points  SAICM focal points (in all but one country)  Basel/Rotterdam/Stockholm Convention (focal points all but one country)  Poisons centres in India, Indonesia, Myanmar, Sri Lanka, Nepal, & Thailand

29 | Chemicals burden of disease |

30 April 2020

Capacity-building initiatives supported from international sources



SAICM Quick Start Programme

– 12 projects value -2.8 M USD • • • National chemicals management plans Lead waste recycling/PCBs/lead Management of priority carcinogens in Thailand (focus on asbestos –Bureau of Environment & Occupational Disease) 

GEF funded initiatives

– – 11M USD – Health-CareWaste initiative (includes India) 32 M USD - Under consideration – sustainable alternatives to DDT in vector management (incl Thailand & Sri Lanka) – Currently funding available for initial implementation activities for implementation of Minamata Convention on Mercury 

Basel, Rotterdam, Stockholm technical assistance 30 | Chemicals burden of disease |

30 April 2020

In conclusion

 Region faces a large burden of disease that can be attributed to chemicals, is very rapidly industrializing, question arises whether ability to manage chemicals is growing at same rate.

 Special conditions are faced by region, informal sector, exposure of vulnerable groups women & children. High reported exposures of chemicals known to be highly hazardous (obsolete in other parts of world).  Available data shows countries are taking measures to address the need for stronger chemicals management – but much remains to be done

31 | Chemicals burden of disease |

30 April 2020

Thank you

32 | Chemicals burden of disease |

30 April 2020