Heavy metals in vegetables and the health risk to population in Zhejiang, China

Overview

Huang and colleagues measured arsenic, cadmium, mercury, and lead in 343 vegetable samples from Zhejiang province, China. The source reports mean and P97.5 concentrations in mg/kg fresh weight, plus counts above Chinese maximum allowable concentrations. Arsenic and mercury are reported as total arsenic (As) and total mercury (Hg) only; no inorganic arsenic or methylmercury speciation is provided.

Key numbers

Table 2 reports concentrations of heavy metals in vegetables from Zhejiang province in mg/kg:

Additional source-reported numbers:

• The abstract states mean levels of As, cadmium (Cd), Hg, and lead (Pb) were 0.009, 0.015, 0.003, and 0.022 mg/kg, respectively.
• The results section specifies the basis as mg/kg fresh weight.
• The study reports that 4.37% of samples exceeded the Cd MAC, 2.62% exceeded the Hg MAC, and 3.79% exceeded the Pb MAC; all samples were within the As MAC.
• The highest mean As and Cd levels by vegetable type were both in rape, at 0.022 and 0.046 mg/kg.
• The highest mean Hg level was in parsley at 0.029 mg/kg.
• The highest mean Pb level was in spinach at 0.056 mg/kg.
• The exposure table reports estimated vegetable intake of 273.3 g/day/person.
• Table 3 reports daily intake assessment values in µg/kg bw/day: As mean 0.04 and P97.5 0.71; Cd mean 0.07 and P97.5 1.48; Hg mean 0.01 and P97.5 0.142; Pb mean 0.11 and P97.5 1.27.
• Table 3 reports health hazard index values: As mean 0.01 and P97.5 0.24; Cd mean 0.09 and P97.5 1.85; Hg mean 0.10 and P97.5 1.01; Pb mean 0.07 and P97.5 0.84.
• The analytical LODs of As, Cd, Hg, and Pb were 0.005, 0.001, 0.005, and 0.005 mg/kg, respectively.

Methods (brief)

The study collected celery (52), asparagus (28), bamboo shoots (30), cabbage (25), Chinese cabbage (30), pakchoi (22), spinach (43), rape (37), tomato (21), eggplant (24), and cucumber (31) samples from Zhejiang, China, between March and October 2012. Samples were stored at 4 °C and analyzed within 24 h after nitric-acid/hydrogen-peroxide digestion. Cd and Pb were measured by graphite-furnace atomic absorption spectrometry on a Thermo SOLAAR iCE3000; As and Hg were measured by hydride generation-atomic fluorescence spectrometry. Below-LOD values were assigned one-half LOD for mean calculations where the proportion below LOD was not greater than 60%.

Implications

This source contributes China-market occurrence evidence for total As, Cd, total Hg, and Pb in fresh vegetables. The eleven sampled types are leafy (cabbage, Chinese cabbage, pakchoi, spinach, rape), stalk/shoot (celery, asparagus, bamboo shoots), and fruit-vegetable (tomato, eggplant, cucumber); no root or tuber vegetables were sampled, so this source does not contribute to root/tuber-vegetable pooling. The concentrations are fresh-weight values and should not be mixed with dry-weight produce studies without an explicit basis conversion. Because arsenic and mercury are reported only as total elements, this page is not suitable for inorganic-arsenic or methylmercury-specific pooling.

Related evidence

• Vegetables
• Leafy Vegetables
• Non-root vegetables
• Leafy / Green Vegetables, Other
• Non-Root Vegetables
• Arsenic, Total
• Cadmium
• Mercury, Total
• Lead

Update history

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