Effect of acetate on lead toxicity to microbial biomass in a red soil

A laboratory incubation experiment was conducted to elucidate the effect of acetate on lead bioavailability and toxicity to microbial biomass in a red soil. Results indicated that the application of acetate along or at the lower lead levels of 100 and 200 μg/g soil stimulated the soil microbial biomass. The addition of acetate at the higher lead levels of 300, 450 and 600 μg/g soil caused significantly greater reductions in the biomass carbon(C mic ) and the biomass nitrogen (N mic ), compared with the control or the same lead levels applied individually. A greater increase in the biomass C:N ratio occurred by acetate addition at the same lead levels. The concentration of 0.01 mol/L CaCl 2 extractable lead was considerably higher in the lead plus acetate treatments than at the same lead levels with no acetate. Based on these results, it was concluded that the application of acetate might have suppressed the lead adsorption in the soil which in turn resulted in its more bioavailability and hence more toxicity to the soil microbial biomass.

Microglia and astroglia:the role of neuroinflammation in lead toxicity and neuronal injury in the brain

Lead(Pb^(2+)),a ubiquitous environmental toxicant,may widely affect the function of many organs or systems of human beings,especially the brain.Although lead is believed to transport into the brain through the blood-brain barrier(BBB)and cause direct neuronal injury,growing data have shown that lead exposure could induce brain dysfunction by triggering microglial and astroglial activation,pro-inflammatory cytokine production and inflammatory response,generation of reactive oxygen species and oxidative stress,and finally result in BBB dysfunction and neuronal damage.This review summarizes recent studies regarding microglial and astroglial reaction,neuroinflammation,and neuronal death in the brain following lead insult,suggesting that reactive glial cells may represent a potential target for manipulation of lead-induced neuroinflammatory injury of the brain.

Reply to 'Statistical testing and distribution for lead chloride toxicity'

We are very grateful for the letter written by Dr Lange,and indeed apologize for the mistakes noted in the word-ing of our text regarding statistical analysis.This wasdue to changes carried out while revising the manuscriptat the request of reviewers,whom we thank for,point-ing out several issues that were actually similar to thosenoted by Dr.Lange.Unfortunately,we were unable todescribe and discuss our findings properly in the context

Effects of lead(Pb)-induced oxidative stress on morphological and physio-biochemical properties of rice

In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils.In the current study,we evaluated four different rice cultivars for their response to Pb-induced stress.Three japonica type cultivars X-Jigna,Ediget,and Furat,and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations(0 mM,0.6 mM,and 1.2 mM).The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation.Thereafter,four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity.The data revealed that a highest concentration of Pb(1.2 mM)induced significant reduction in agronomic traits such as plant height,number of tillers per plant,number of panicles per plant,and number of spikelets per panicle in all the rice cultivars.However,least reduction in the agronomic traits was observed in X-Jigna,whereas the highest reduction in the agronomic traits was observed in Ediget.Antioxidant activity of catalase(CAT),peroxidase(POD),polyphenol oxidase(PPO),and superoxide dismutase(SOD),was evaluated along with the accumulation of superoxide ions(O2.-),protein,proline,chlorophyll,sucrose,glucose,and fructose contents in all the rice cultivars.A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress.On the other hand,non-significant and slightly significant increase in the antioxidant activity,less accumulation of proline and sucrose contents,and higher reduction in the chlorophyll and protein contents was observed in Ediget,which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress.In addition,the other rice cultivars Furat and Amber 33,were found to be moderately tolerant to Pb-induced oxidative stress.In summary,our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems,leading to a balanced redox status in rice.

Lead chemisorption:Paving the last step for industrial perovskite solar cells

Perovskite solar cells(PSCs)have exhibited impressive performance,achieving a power conversion efficiency(PCE)of 26.1%.However,the water-soluble and toxic nature of lead(Pb)in PSCs hinders their industrialization.Pb chemisorption has emerged as a promising approach to address this issue to prevent Pb leakage and ensure long-term stability.This perspective provides a comprehensive overview of recent advancements in Pb chemisorption in PSCs and discusses the prospects for future developments and challenges in this field.