Transcript MRA in China - FoodRisk.org
Microbiology Risk Assessment in China:
Current Situation & Challenges
Xiumei Liu
Institute of Nutrition and Food Safety China CDC
July 25,2002 1
Risk Analysis
July 25,2002
Risk assessment Risk management Risk communication
2
RA
RM A scientifically based process The process of weighing policy alternatives, distinct from risk assessment
July 25,2002 3
MRA in the Word
Foodborne bacteria
Risk Assessment Risk Management FAO/WHO （ JEMRA ） Codex （ CCFH ）
Mycotoxins, metabolites of fungi
Risk Assessment FAO/WHO （ JECFA ） Risk Management Codex （ CCFAC ） July 25,2002 4
China Activities in MRA
CCFH
Since 32 nd 1999 JEMRA
Since 2000, Food hazard, EA, QMRA
CCFAC
Over 10 years, 32 nd 2000 in Beijing JECFA
Expert and data contribution (AF, Fumonisin, DSP)
July 25,2002 5
Why MRA is needed in China
？ WTO CODEX / GB FOOD INDUSTRY FOOD SAFETY CONTROL Government Consumers HEALTH PROTECTION Life quality knowledge July 25,2002 6
Risk Assessment
Hazard Identification Hazard Characterization Exposure Assessment Risk Characterization
July 25,2002 7
Hazards in Food
Foodborne bacteria
Fungi and mycotoxins
Viruses and parasites Toxic plants and animals Potential environmental toxicants July 25,2002 8
Foodborne bacteria in China
Pathogens Salmonella Bacillus cereus Burkholderia cocovenenans Proteus Staphylococcus aureus Clostridium botulinum Escherichia coli Vibrio parahaemolyticus Mortality (%) 0.1
0.037
40 0.03
0.045
7.3
0.1
0.01
(1990-1996) July 25,2002 9
1933
1960
1950’s
1979
1984
1987 1995
July 25,2002
Case 1
BA Food Poisoning Control
Indonesia: Fermented coconut food poisoning
Pseudomonas cocovenenans
Bongkrekic acid
China: Unknown causes fermented corn flour poisoning
Flavobacterium farinofermentans nov. sp
China: Deteriorated tremella poisoning,
P. cocovenenans subsp. farinofermentans
Burkholderia cocovenenans (B. gladiali)
10
Bongkrekic acid Food Poisoning Caused by Various Food in China Food _______________________________________________________________ Cereal products Provinces Outbreaks Patients Fatal Mortality 12 78 cases (%) 499 238 62.12
Deteriorated tremella Potato product 5 3 22 3 148 20 54 9 36.49 45.00
Total 16 103 667 301 45.13
_______________________________________________________________ (1985-1994)
July 25,2002 11
Hazard identification: Bongkrekic acid, BA
Molecular formula
C28H38O7
Target Organs
LD50
3.16mg/kg
Liver Brain Kidney
July 25,2002 12
Studies on the last 15 years l
Identification and examination of the foodnorne pathogen
l
Identification analysis and detoxication of BA
l
Diagnosis, monitor and prevention of food poisoning
July 25,2002 13
Risk Manegement in China
GB/T 4789.29-94
Examination of
P. cocovenenans
subsp.
Farinofermentans
GB 11675-89
Hygienic Standard of Tremella (BA Detection method)
GB WT/12-96
Diagnostic Criteria and Principle of Management for
P. Cocovenenans
subsp.
farinofermentans
Food Poisoning July 25,2002 14
BA poisoning control
Outbreaks of BA reduced about 80% in 1990
’
s.
July 25,2002 15
Prevalence in fly feces Mean: 11.9% 5 th -95 th : 10.7%-13.1%
Prevalence
Fig Distribution for E.coli prevalence in fly feces —— Beta(235,1988-235+1)
July 25,2002 16
July 25,2002 Month Mar Apr May June July Aug Sep
Number of houseflies
Average flies density （ no. of flies/cage · day ） 21 63 125 221 314 341 257 17
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0 0
No. of ingested bacteria
Mean: 310 cfu/meal 5 th -95 th : 23
～
875cfu/meal
1000 2000 Number of ingested bacteria 3000 July 25,2002 18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0 0.54
Exposure probability
0.59
Mean: 63.5% 5 th -95 th : 59.5%
～
67.4%
0.64
0.69
Exposure probability 0.74
July 25,2002 19
Natural toxicants --
Actual and potential effects in humans
Acute effects liver illness, poisoning, death
Aflatoxin,
DON,
3-NPA,
Ergot
Microcystin,
Saxitoxins, Domoic acid, Solanine Chronic effects Carcinogenic, genotoxic & endemic illness
Aflatoxins,
Fumonisins, Deoxynivalenol, Zearalenone, Ochratoxin A, Patulin , T-2 toxin, Moniliformine, Sterigmatocystin Microcystin, Domoic acid, Cyanogenic glycosides July 25,2002 20
Example:
Aflatoxin B
1
Animal toxicity data showed: it could cause primary liver cancer in most species studied Epidemiological studies found an association between consumption of food contaminated with aflatoxin B 1 and liver cancer Is a genotoxic carcinogen July 25,2002 21
Quantitative risk assessment at 49
th
JECFA Meeting
HBsAg ( ＋ ) :0.3 liver cancer/year/100,000/ ng AF/ kg bw/day HBsAg ( － ) :0.01 liver cancer /year /100,000 / ng AF/kg bw/day July 25,2002 22
HBsAg(
＋
) 1%; European Cont. level & Dietary Pattern
AFB1 intake Risk (ng/day) (Cancer/year/100,000) AFB1 limit 20 µ g/kg 19 0.0041 (0.0006-0.01) AFB1 limit 10 µ g/kg 18 0.0039 (0.0006-0.01) 2 cancers/year/billion July 25,2002 23
China cont. level and far east dietary pattern
AFB1 intake Risk (ng/day) (Cancer/year/100,000) AF limit 20 µ g/kg 125 0.17 (0.03-0.3) AF limit 10 µ g/kg 103 0.14 (0.02-0.3) 300 cancers/year/billion *The mortality of liver cancer was 20/100,000 in the period of 1990-1992.
(20.03/100,000) July 25,2002 24
Case 2
The Control of the Deteriorated Sugarcane Food Poisoning in China Fresh sugarcane grown in southern area of China Usually shipped to northern parts of China, stored and sold through the winter season Contaminated sugarcane can cause fatal food poisoning when sold in the next spring July 25,2002 25
Sugarcane poisoning
The first outbreak of sugarcane poisoning with unknown causes occurred in Henan Province in 1972 From 1972 to 1989:
No. of outbreak: 217 No. of cases: 884 No. of deaths: 88 Average fatality: 10%
Identified as a priority to assess and control July 25,2002 26
Characteristics of 34 MSP Cases
Age: Incubation period: Manifestations: 3 to 27 years old 10 minutes to 8 hours Vomiting Dystonia Stare on one side Convulsion Carpopedal spasm Coma Electroencephalogram Sequelae July 25,2002 27
Etiology and risk assessment
Etiology: the Chinese Academy of Preventive Medicine studied on the etiology of this specific food poisoning since 1984 and found: Arthrinium spp.
was the pathogenic fungus; 3-nitropropionic acid (3-NPA) produced proved to be the causative compound by A. spp.
was Assessment was made according to case-based studies, epidemiological and laboratory studies July 25,2002 28
Decision making and management activities
Based on discovery and assessment, MOH promulgated :
Diagnostic criteria and principles for the management of deteriorated sugarcane poisoning (WS/T10-1996); Methods for the isolation and identification of strains Arthrinium and analyzing 3-nitropropionic acid (GB47689.16)
At the same time, MOH issued a notification on the prevention and control of DSP to all provinces of China A national health campaign for prevention and control of the poisoning was launched July 25,2002 29
Prevention and control measures
The main measures adopted by local health inspectors: Fresh sugarcane shipped to northern China should not be stored for more than 3 weeks The deteriorated sugarcane with unpleasant smell and mold growing should not be sold in market When poisoning outbreak occurred, the suspected left-over sugarcane should be immediately sealed and destroyed During the outbreak, food inspectors and clinical doctors should work closely to identify and treat patients July 25,2002 30
Good results
As a result of these efforts, sugarcane poisoning has been satisfactory controlled No typical cases were reported in China in the last 10 years!
July 25,2002 31
Challenges: Areas for Strengthening
Knowledge Team Practice
（
National level
） （
Data, Modeling
） Food consumption / dietary intake Effects of processing
QMRA
Analytical methods Sampling protocols
(Quantitative method)
July 25,2002 32
FAO/WHO Activates in China
Workshop on Microbiological Risk Assessment
Sponsored by FAO/ ILSI /WHO/ MOH May 10-11, 2002 Beijing
Quantitative Microbiological Risk Assessment Training Course (David Vose)
Sponsored by WHO/INFS May 13-24, 2002 Beijing July 25,2002 33