Health risk and temporal trend of dietary potentially toxic elements exposure in the residents of the Shenzhen metropolis, China, between 2005 and 2017: a risk assessment based on probabilistic estimation.

Dietary potentially toxic elements (PTEs) exposure in developing countries is of great concern. Probabilistic estimation exhibits great superiority in risk assessment by dealing with the variability and uncertainty of the parameters. Here, a probabilistic estimation based on two dimensions, PTEs in foods and food intake, was conducted. A total of 13 foods were collected from Shenzhen markets during 2005-2017, and the concentrations of Pb, Cd, Hg, and As were detected. A total of 853 residents from 245 households participated in a total diet study. The mean concentrations of Pb, Cd, Hg and As were 0.046, 0.0196, 0.0038, and 0.029 mg kg-1 in cereals, 0.042, 0.0174, 0.0027, and 0.014 mg kg-1 in vegetables, 0.044, 0.0237, 0.0056, and 0.021 mg kg-1 in meat, and 0.081, 0.1035, 0.0257, and 0.680 mg kg-1 in aquatic products, respectively. The probability density function showed that the 95th percentiles of the Pb, Cd, Hg, As hazard quotients (HQ) and the hazard index (HI) were 0.68, 1.57, 0.38, 5.81 and 7.51, respectively. Cumulative probability and sensitivity analysis showed that cereals and vegetables contributed most to Pb and Cd exposure; aquatic products to Hg exposure; and cereals and aquatic products to As exposure. The results showed that Shenzhen residents were at risk of exposure to Cd, As, and four PTEs in combination, although a temporal decreasing trend was observed. The probabilistic estimation used here reveals a complete picture of multiple PTEs exposure risk and identifies major contributing food categories, providing a valuable means for risk assessment.

[Measuring diet quality of labor workers in Shenzhen using Chinese diet balance index].

OBJECTIVE: To evaluate the overall diet quality and diet model of labor workers in Shenzhen using Chinese Diet Balance Index (DBI). METHODS: In May 2009, 14 canteens from Baoan, Longgang and Nanshan districts were selected by stratified random sampling and 60 workers were randomly selected from each canteen by using random number method. Diet measurements were carried out among the 840 labor workers. Diet quality was evaluated by using DBI scoring and evaluating system. RESULTS: The median values of labor workers' food intakes of cereal and meat & poultry were 483.8 and 121.7 g/d, which were more than the recommended amounts of their intakes of Chinese residents (cereal: 250 - 400 g/d, meat & poultry: 50 -70 g/d). The median values of the labor workers' intakes of fruit, dairy and eggs were 37.3, 20.6 and 23.5 g/d,which were less than recommended amounts in fruits (200 - 400 g/d), dairy (300 g/d) and eggs (25 - 50 g/d). The DBI-HBS scores of males and females in Shenzhen migrant workers were 24.4 +/- 6.1 and 22.6 +/- 6.3, respectively with a statistically significant difference (t = 4.21, P < 0.01). DBI-HBS scores of < 20 age group, 20 - 29 age group, 30 - 39 age group and > or = 40 age group in labor workers were 12.7 +/- 5.9, 11.3 +/- 6.3, 12.8 +/- 6.4 and 11.2 +/- 5.6 respectively (F = 3.67, P = 0.01). There were 7 dietary patterns among labor workers in this survey. Nearly 8.2% (68/830) of them belonged to Pattern A. Pattern B and E were the main dietary patterns, which accounted for 37.3% (310/830) and 31.0% (257/830) of the total population. CONCLUSION: DBI can describe and evaluate the overall dietary quality and the major problem of the dietary patterns in labor workers. It is necessary to strength nutritional education to increase the intake of fruits, milk and eggs to improve nutritional status in labor workers in Shenzhen.

Dietary exposure assessment of paralytic shellfish toxins through shellfish consumption in Shenzhen population, China.

Paralytic shellfish toxins (PSTs) produced by certain marine dinoflagellates accumulate in filter-feeding marine bivalves. We used LC-MS/MS to detect and quantify 13 PSTs in 188 shellfish samples of 14 species collected from Shenzhen city's Buji seafood wholesale market from March 2019 to February 2020. Twenty-six of 188 shellfish samples (13.8%) were PSTs detectable. Within 14 species, 10 out of 34 noble clam Chlamys nobilis samples contain detectable PSTs with the highest detection rate 29.4%. Seven out of 17 samples from Nan'ao island contained detectable PSTs with the highest detection rate 41.2% among 11 origins. Samples containing PSTs were concentrated in spring and winter, with the highest levels in March>December>January. Among PSTs detected, C1 was dominant. Acute dietary exposure assessment for Shenzhen residents were based on mean adult body weight, 99th percentile daily shellfish consumption of Shenzhen food consumption survey 2008 and maximum PSTs concentration for each shellfish species. The outcome for Chlamys nobilis was 2.4~3.7-fold higher than recommended ARfDs. Mean PSTs concentration, P99, and mean shellfish consumption were used to assess chronic dietary exposure. The results were lower than recommended ARfDs. In conclusion, residents in Shenzhen are at risk for acute PSTs poisoning, while relatively safe from chronic PSTs exposure.

Concentrations of PCDD/PCDFs and PCBs in retail foods and an assessment of dietary intake for local population of Shenzhen in China.

OBJECTIVES: Concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 18 polychlorinated biphenyls (PCBs) were measured in 11 varieties of food groups collected from retail market of Shenzhen, Guangdong province, China from 2004 to 2006. PCDD/Fs and PCBs dietary intake from varies food for the local population was estimated in the study. METHODS: Concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (PCBs) as well as 6 marker PCBs were measured in 11 varieties of food groups in total 110 food samples by isotope dilution HRGC/HRMS. PCDD/Fs and PCBs dietary intake for local population was estimated using total WHO-TEQ concentration and different food consumption amount of the local population. RESULTS: The median WHO-TEQ concentrations of sum of PCDD/Fs and DL-PCBs varied from 0.0093 pg/g (parts per trillion) in vegetable to 9.89 pg/g in fish. Fish was followed by egg 2.46, chicken 1.73, beef 0.94, mutton 0.82, duck 0.39, pork 0.37, milk powder 0.25, vegetable oil 0.076, cereals 0.022 pg/g and vegetable. The monthly intake of PCDD/Fs and PCBs were 40.9 pg WHO-TEQ/kg b.w. for local population. Sum of fish, livestock, and poultry contributed 77% to the Estimated Monthly Intake (EMI) in local population. CONCLUSION: Estimated dietary intake of PCDD/Fs and DL-PCBs for local population was below the provisional tolerable monthly intake(PTMI) set by Joint FAO/WHO Expert Committee on Food Additives (JECFA).

Dietary exposure to cadmium of Shenzhen adult residents from a total diet study.

Cadmium (Cd) contamination has become a public health concern in recent decades. The aim of the present study was to assess the contribution of dietary Cd exposure and its health risk among Shenzhen adult residents using the Total Diet Study (TDS) approach. Cd was determined in 13 food groups using 276 individual samples by ICP-MS. The major food contributors to Cd exposure of Shenzhen adult residents were 'Vegetables' (32.6% of the total exposure), 'Rice and its products' (19.2% of the total exposure) and 'Fish, seafood and shellfish' (18.5% of the total exposure). The mean and the 95th percentile dietary exposure to Cd of Shenzhen adults were 9.9 and 13 µg kg-1 bw month-1, respectively. The dietary exposures of all individual age-gender population subgroups were below the provisional tolerable monthly intake (PTMI = 25 µg kg-1 bw month-1), so the health risk of Cd dietary exposure of Shenzhen adults is considered to be low, but still, cadmium pollution should be strictly controlled and monitored continuously due to an exceptionally long biological half-life of cadmium.

Dietary exposure to lead of adults in Shenzhen city, China.

Lead, a ubiquitous heavy metal, can be found in the environment and food. The present study is the first to estimate the lead dietary exposure of Shenzhen adults (≥ 20 years old) in various age-gender subgroups, and to assess the associated health risk. Food samples that represented the Shenzhen people's dietary pattern were collected and prepared for analysis. Lead was determined in 13 food groups using 276 individual cooked samples by inductively coupled plasma-mass spectrometry (ICP-MS). Dietary exposures were estimated by combining the analytical results with the local food consumption data of Shenzhen adults. The mean and 95th percentile lead exposure of Shenzhen adults were 0.59-0.73 and 0.75-0.94 µg kg(-1) bw day(-1), respectively. In all food groups, the highest lead exposure was from 'Eggs and their products' (42.4-51.6% of the total exposure); preserved eggs being the main contributor. The other major contributors to lead exposure of Shenzhen adults were 'Fish and seafood, and their products' (14.3-16.7% of the total exposure) and 'Vegetables and their products' (15.5-16.2% of the total exposure). The margin of exposure (MOE) approach was used for the risk assessment of lead, and the results showed that the risk was considered to be low in all age-gender groups for Shenzhen adults. However, having considered a number of toxic effects of lead, it is suggested that more efforts should be made to reduce the lead levels in foodstuff for Shenzhen adults.