Springer Science and Business Media LLC

Half-life of urinary cadmium level (U-Cd) was estimated in inhabitants whose initial U-Cd was ≥5 μg/L (131 men and 177 women) or ≥5 μg/gcr (195 men and 246 women), using a linear mixed model adjusted for the baseline age. To clarify the effect of initial U-Cd, the target participants were divided into higher or lower initial U-Cd group. In the higher groups, the half-lives were 15.4 and 13.1 years for unadjusted U-Cd and 19.0 and 23.0 years for creatinine-adjusted U-Cd, in men and women, respectively. In the lower groups, the half-lives were 38.0 and 26.0 years for unadjusted U-Cd in men and women. For creatinine-adjusted U-Cd, it was 42.9 years in men. For attenuation of U-Cd, there were an early fast component shown in the higher group and late slow component shown in the lower group. The attenuation of U-Cd is slower in the longer time compared to that previously reported.

The purpose of this greenhouse study was to assess the capacity of vetiver grass to accumulate arsenic from pesticide-contaminated soils of varying physico-chemical properties. Results indicate that vetiver is capable of tolerating moderate levels of arsenic up to 225 mg/kg. Plant growth and arsenic removal efficiency was strongly influenced by soil properties. Arsenic removal was highest (10.6%) in Millhopper soil contaminated with 45 mg/kg arsenic, which decreased to 4.5 and 0.6% at 225 and 450 mg/kg, respectively. High biomass, widespread root system and environmental tolerance make this plant an attractive choice for the remediation of soils contaminated with moderate levels of arsenic.

Plantlets of Pfaffia glomerata (Spreng.) were exposed in vitro for 30 days to five lead levels (0–400 μM) to analyze the effects on growth and oxidative stress and responses of various antioxidants vis-à-vis lead accumulation. The plantlets showed significant lead accumulation in roots (1,532 μg g−1 DW) with a low root to shoot lead translocation (ca. 3.6%). The growth of plantlets was negatively affected by various lead treatments, although the level of photosynthetic pigments did not alter significantly in response to any lead treatment. However, plantlets suffered from oxidative stress as suggested by the significant increase in malondialdehyde levels in root (8.48 μmol g−1 FW) and shoot (3.20 μmol g−1 FW) tissues with increasing lead treatments. In response to the imposed toxicity, increases in the activities of catalase in root (4.14 ∆E min−1 mg−1 protein) and shoot (3.46 ∆E min−1 mg−1 protein) and superoxide dismutase in root (345.32 units mg−1 protein) and shoot (75.26 units mg−1 protein), respectively, were observed, while the levels of non-protein thiols and ascorbic acid were not affected significantly in either roots or shoots.