Objectives: To assess levels of dioxin in food and human blood and determine the relationship between levels of dioxin in food and human blood in some areas of Vietnam. Subjects and method: A cross-sectional study on 108 human blood samples including males and females, 33 samples of chicken, 33 samples of pork and 33 samples of fish were collected at 33 sites in 16 provinces.
Trang 1RELATIONSHIP BETWEEN LEVELS OF DIOXIN IN FOOD AND
BLOOD IN SOME AREAS OF VIETNAM
Vu Tung Son*; Doan Huy Hau*
Vu Chien Thang*; Ha The Tan*
SUMMARY
Objectives: To assess levels of dioxin in food and human blood and determine the relationship between levels of dioxin in food and human blood in some areas of Vietnam Subjects and method: A cross-sectional study on 108 human blood samples including males and females, 33 samples of chicken, 33 samples of pork and 33 samples of fish were collected
at 33 sites in 16 provinces Samples were then quantified with high resolution gas chromatography mass spectrometry (HRGC/HRMS) by the U.S EPA 1613 B Result: Levels of dioxin in blood in the sprayed area was (10.34 pg/g lipid) higher than in the unsprayed area (6.94 pg/g lipid) with p < 0.05 The levels of dioxin in blood in the dioxin-contaminated area was (9.62 pg/g lipid) higher than in the non-contamination area (8.24 pg/g lipid) with p < 0.05 For food, chicken had the highest dioxin content Chicken and pork were positively correlated with dioxin content in human blood Conclusion: Levels of dioxin in blood in the area sprayed with herbicides was higher than in the unsprayed area Similarly, they were higher in the dioxin contamination than in the non-contamination area Chicken and pork have positive corelation with dioxin content in human blood
* Keywords: Dioxin; Dioxin in food; Dioxin in blood; Relationship.
INTRODUCTION
Persistent organic pollutants (POPs)
include a group of pollutants that are
semi-volatile, persistent in the environment,
bio-accumulative and toxic for humans
and aminals Two groups of POPs, namely
polychlorinated dibenzo-p-dioxins (PCDDs),
poly-chlorinated dibenzofurans (PCDFs)
and polychlorinated biphenyls (PCBs) are
persistently organic pollutants of great
concern because of their high toxicity and
tendency to bioaccumulate through the food chain These contaminants can be formed as unintentional by products of a number of chemical processes, as well as
in almost combustion process More than
90 percent of dioxin penetrates the human body through food Therefore, the aim of
this study is: To evaluate the relationship
between levels of dioxin in food (chicken, pork and fish) and those in blood in several regions of Vietnam
* Vietnam Military Medical University
Corresponding author: Vu Tung Son (tungsonhvqy@gmail.com)
Date received: 11/09/2017
Trang 2SUBJECTS AND METHODS
1 Subjects
- The first subject: People who have
lived in study area for at least 15 years
(no occupational exposure to dioxin), including
males and females After that, they were
taken blood to quantify levels of dioxin
- The second subject: Food (chicken,
pork and fish) which was collected at the
same area; blood samples (food specimens
were collected in the lake or market)
Afterward, they were quantified levels of
dioxin
2 Methods
33 samples of chicken, 33 samples of
pork, 33 samples of fish and 108 samples
of blood were collected in 33 wards of
16 provinces in Vietnam (Hoabinh, Hagiang,
Thainguyen, Ninhbinh, Thanhhoa,
Nghean, Quangtri, Hue, Lamdong,
Kontum, Hochiminh City, Binhduong,
Dongnai, Longan, Kiengiang, Angiang)
Samples were selected based on the characteristics of each region The areas were sprayed with herbicides during the war (from the 17th parallel to the south, which was encrypted “B”) and the area was unsprayed with herbicides during the war in Vietnam (from the 17th parallel to the North, which was encrypted “A”)
In turn, each area was divided into those
at risk of dioxin contamination, which was encrypted “1” (industrial production area
or the area was sprayed directly with herbicides) and those without dioxin contamination, which was encrypted “0”
At each sampling point, each food was taken from 6 to 10 specimens and then were pulled to one sample For blood specimen, each person was taken 10 mL whose blood samples were grouped by age and gender
The sample size and sampling according
to US EPA (United States Environmental Protection Agency) guidelines
Encode:
A The area was not sprayed with herbicides during the war in Vietnam
B The areas were sprayed with herbicides during the war
AB-0 Areas are non-dioxin contamination at both A or B
AB-1 Areas were at risk of dioxin contamination at both A or B
* Analysis:
Quantification 7 PCDD (polychlorinated dibenzo para dioxins) and 10 PCDF (polychlorinated dibenzofurans) in blood and food by method US EPA 1613B, then compute WHO TEQ concentrations (toxic equivalents)
Trang 3RESULTS
Table 1: Levels of PCDD/F (TEQ) in blood by region
TEQ (pg/g lipid)
p-value
< 0.001
Average TEQ was 9.21 pg/g lipid; average TEQ in blood at the areas which were sprayed with herbicides during the war was 10.34 pg/g lipid higher significantly than the area without herbicides in the same period (6.94 pg/g lipid) (p < 0.001)
Table 2: Levels of PCDD/F (TEQ) in blood by contaminated areas
TEQ (pg/g lipid)
p-value
0.04
Average TEQ in blood in the area at risk of dioxin contamination (AB-1) was 9.26 pg/g lipid, higher significantly than those without dioxin contamination (AB-0) (8.24 pg/g lipid) (p < 0.05)
Table 3: Levels of PCDD/F (TEQ) in chicken, pork and fish by region
TEQ (pg/g)
p
Chicken (pg/g lipid)
0.005
Pork (pg/g lipid)
0.07
Fish (pg/g wet weight)
0.4
Average TEQ in chicken, pork and fish in the areas sprayed with herbicides was higher than those unsprayed with herbicides However, only TEQ in chickens were different significantly with p < 0.05
Trang 4Table 4: Levels of PCDD/F (TEQ) in chicken, pork and fish by contaminated areas
Average TEQ in food in the area at risk of dioxin contamination (AB-1) was higher than non-contamination dioxin area (AB-0) However, there was no significant difference between the two regions with p > 0.05
Table 5: Corelate Pearson between TEQ in chicken, pork and fish and TEQ in blood
Levels of dioxin
(pg/g lipid)
TEQ
Number size
TEQ in blood were positively corelative to TEQ in chicken and pork (p < 0.05) with r = 0.25 and 0.2, respectively
Table 6: Correlate Pearson between TEQ in chicken, pork and fish and TEQ in
blood by region
TEQ in blood
by region
Number size
TEQ
TEQ in blood were positively associated with fish at unsprayed areas (p < 0.05) with
r = 0.38
TEQ (pg/g)
p
Chicken (pg/g lipid)
0.4
Pork (pg/g lipid)
0.08
Fish (pg/g wet weight)
0.6
Trang 5Table 7: Correlate Pearson between TEQ in chicken, pork and fish and TEQ in
blood by contaminated areas
TEQ in blood by
contaminated areas
Number size
TEQ
TEQ in blood were positively associated with fish at unsprayed areas (p < 0.05) with r = 0.46 and chicken at sprayed area (p < 0.05) with r = 0.3
DISCUSSION
The results showed that the content of
TEQ dioxin in our study was from several
times to dozens of times lower than that
in the study by the Hatfield Consultants
and Office of National Committee 33 in
Bienhoa Airport and Phucat Airport which
were reported in 2009 (5.64 - 8.350 pg/g
wet weight in fish) and 2011 (4.54 - 4,050 pg/g
wet weight in fish), respectively Because
the samples in the study by Hatfield and
Office 33 were taken in the dioxin hotpot
[1, 2] Compared with 187 studies by
Dario Consonni on 29,687 subjects from
26 countries in the world for 10 years
(1989 to 2010), our results were lower
than that his study (12.4 pg/g lipid) [3]
In terms of food, a monitoring study in
Latvia from the year 2009 - 2011 showed
that the TEQ content of chicken in both
sprayed and non-sprayed areas was
0.78 pg/g lipid, lower than that in our study
(4.41 and 1.8 pg/g lipid, respectively)
Specificially, TEQ content in all chicken
samples reached the allowable limit As
for pork, the TEQ content in our study
was (0.28 pg/g lipid) also higher than that
in above study and no pork samples with TEQ content exceeded the allowable limit For fish, the TEQ content in our study in both regions was lower than fish specimens
in Baltic (2.25 pg/g lipid), but our results were higher than fish samples in the ocean (0.11 pg/g lipid) In the monitoring study in Latvia, TEQ content in chicken was higher than in other types of meat, too [4]
Levels of dioxin in chicken, pork and fish were related those in blood depending
on the region and characteristics In particular, the content of chicken and pork had a statistically significant association with levels of dioxin in blood However, in terms
of characteristics, there was a positive corelation between dioxin content in fish and human blood in the areas unsprayed with herbicides When analyzing the dioxin-contaminated characteristics, there was a positive association between dioxin concentration in fish and blood in the non-contaminated dioxin area, meanwhile in dioxin-contaminated areas, there was also
Trang 6a positive correlation between dioxin content
in chicken and human blood
CONCLUSION
The level of dioxin in blood in the
sprayed areas was (10.34 pg/g lipid)
higher than in the unsprayed areas (6.94
pg/g lipid) (p < 0.001) The levels of dioxin
in blood in the dioxin-contaminated areas
was (9.62 pg/g lipid) higher than in the
non-contamination areas (8.24 pg/g lipid)
with p < 0.05 Chicken and pork have
positive correlation with dioxin content in
human blood
REFERENCES
1 Hatfield Consultants, Office of National
Committee 33 Comprehensive assessment of
dioxin contamination in Danang Airport, Vietnam:
Environmental levels, Human exposure and
options for mitigating impacts Hatfield Consultants West Vancouver British Columbia, Canada and Office of National Committee 33, MONRE Hanoi, Vietnam 2009
2 Hatfield Consultants, Office of the National Steering Committee 33, MONRE
Environmental and human health assessment
of dioxin contamination at Bienhoa Airbase, Vietnam 200 - 850 Harbourside Drive, North Vancouver, British Columbia, Canada V7P 0A3
2011
3 Consonni D, Sindaco R, Bertazzi P.A
Blood levels of dioxins, furans, dioxin-like PCBs, and TEQs in general populations: a review
1989 - 2010 Environment International 2012,
44, pp.151-162
4 Zacs D, Bartkevics V Polychlorinated
dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in food and feed
in Latvia in 2009-2011 Food Additives & Contaminants Part B, Surveillance 2014, 7 (3), pp.186-220