benefits and drawbacks of strict regulation on chemicals
TRANSCRIPT
Benefits and drawbacks of strict regulation on chemicals
Michael Eddleston
Pharmacology, Toxicology & Therapeutics, University of Edinburgh
National Poisons Information Service - Edinburgh
South Asian Clinical Toxicology Research Collaboration - SACTRC
Edinburgh Clinical Toxicology
Pesticide self-poisoning in rural Asia
Pesticide self-poisoning kills about 150-200,000 people every year
WHO: major global means of suicide
Singh & Tyagi 1999
1972-77 1977-82 1982-87 1987-92 1992-97
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50
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Aluminium phosphide
All poisoning death
Num
ber o
f dea
ths
Household use of aluminium phosphide, north India
www.worldmapper.org
What is the consequence of pesticide self-poisoning?
www.worldmapper.org
A distorted global burden of fatal intentional self-harm
Occupational poisoning
Occupational poisoning
But WHO Toxicity Class is important –
not a major problem with relatively
less toxic Class II pesticides
CKDu
CKDu
Solutions to this very real problem?
William Haddon, Jr Head of the US National Highway Traffic Safety Admin Invented the Haddon Matrix for risk reduction in 1970 - Pre-event - Event - Post-event
Hazard Reduction or Harm Minimisation
1. Improving medical care
2. Administrative controls
3. Engineering controls
Harm minimisation to reduce deaths from pesticide poisoning
Improve medical care
Organophosphorus insecticides
• worldwide, 3-6,000 people are currently being ventilated
But resource implications are too large
Clinical care can be useful - identifying high risk chemicals
Bedside observation -> toxicological stratification
•Eddleston et al, Lancet 2005
1. Improving medical care
2. Administrative controls
3. Engineering controls
Harm minimisation to reduce deaths from pesticide poisoning
Administrative controls – agriculture extension
Administrative controls – agriculture extension
1. Improving medical care
2. Administrative controls
3. Engineering controls
Harm minimisation to reduce deaths from pesticide poisoning
Administrative control
IASP 2005:
“Recently, experience has shown
that providing for safer storage of
pesticides may be a particularly
effective method [of preventing
pesticide poisoning deaths].”
Administrative controls – “Safe Storage”
Bayer 2015:
“Reduced access to [pesticides]
– keeping them locked with
limited access – helps avoid
many poisonings and deaths”
Recruitment:
223,857 individuals
53,379 households
• Three studies from Sri Lanka and India suggest that 15-20%
of pesticides are purchased
from a shop specifically for the
act
• Improved storage might make
things worse, as household
pesticides became less
accessible
Source of pesticides taken in overdose?
P1
S1
S2 S4 S3
Vendor interventions may be an important approach
1. Improving medical care
2. Administrative controls
3. Engineering controls
Harm minimisation to reduce deaths from pesticide poisoning
A minimum pesticides list
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1880 1886 1892 1898 1904 1910 1916 1922 1928 1934 1940 1946 1952 1958 1964 1970 1976 1982 1988 1994 2000
Suicide rates in Sri Lanka 1880-2005
Year
Gunnell et al Int J Epi 2009
Engineering controls – might these work?
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1880 1886 1892 1898 1904 1910 1916 1922 1928 1934 1940 1946 1952 1958 1964 1970 1976 1982 1988 1994 2000Year
All class I pesticides banned 1995
Endosulfan Banned 1998
Parathion / methyl parathion banned 1984
Regulation of Highly Hazardous Pesticides
Reducing access to highly lethal means will reduce deaths from suicide
Cereals
1980 1985 1990 1995 2000 20050
1000
2000
3000
4000
BangladeshIndiaPakistanSri Lanka
Year
kg/h
ecta
re
Pulses
1980 1985 1990 1995 2000 20050
200
400
600
800
1000
Year
kg/h
ecta
re
Roots & tubers
1980 1985 1990 1995 2000 20050
5000
10000
15000
20000
Year
kg/h
ecta
re
Manuweera et al EHP 2009
Yes, fine, but this will cause food shortages!!
Agricultural yield in South Asian
countries between 1980 - 2005
Manuweera et al EHP 2009
Paddy production in NCP 1990-2005
Hasn’t this only happened in Sri Lanka – Unique Case?
Estimates for pesticide suicides have fallen from • 180,000 in
1995-2000 to • 55,000 now
1995 2000 2005 2010 20150
2,000
4,000
6,000
8,000
1400016000
1800020000
Pesticide related suicideHangingOther unnatural deathTotal unnatural deaths
Year
Num
ber
of d
eath
s
Previously: • Jordan • Samoa
1. Improving medical care
2. Administrative controls
3. Engineering controls
Conclusion
Chemicals regulation works as a
highly effective intervention to
reduce risks from use of
chemicals
As is apparent from our
experience of public health
interventions, engineering
controls are going to be the
most effective approach