Toksični učinci olova u profesionalno izložene indijske obitelji

This article describes an entire family manufacturing lead acid batteries who all suffered from lead poisoning. The family of five lived in a house, part of which had been used for various stages of battery production for 14 years. Open space was used for drying batteries. They all drank water from a well located on the premises. Evaluation of biomarkers of lead exposure and/or effect revealed alarming blood lead levels [(3.92±0.94) µmol L-1], 50 % reduction in the activity of δ-aminolevulinic acid dehydratase [(24.67±5.12) U L-1] and an increase in zinc protoporphyrin [(1228±480) µg L-1]. Liver function tests showed an increase in serum alkaline phosphatase [(170.41±41.82) U L-1]. All other liver function test parameters were normal. Renal function tests showed an increase in serum uric acid [(515.81±86.29) µmol L-1] while urea and creatinine were normal. Serum calcium was low [(1.90±0.42) mmol L-1 in women and (2.09±0.12) mmol L-1 in men], while blood pressure was high in the head of the family and his wife and normal in children. Lead concentration in well water was estimated to 180 µg L-1. The family was referred to the National Referral Centre for Lead Poisoning in India, were they were received treatment and were informed about the hazards of lead poisoning. A follow up three months later showed a slight decrease in blood lead levels and a significant increase in haemoglobin. These findings can be attributed to behavioural changes adopted by the family, even though they continued producing lead batteries.Olovo je sveprisutni metal s mnogo namjena, a čovječanstvo ga rabi već više od 6000 godina. Danas je olovo među najrasprostranjenijim toksinima u okolišu, a drugi je na popisu toksičnih metala, odmah iza arsena. Mnogi još nisu svjesni njegova toksičnoga djelovanja te se i dalje izlažu olovu. Ovdje je opisana obitelj koja proizvodi olovne akumulatore i koja je pretrpjela trovanje olovom zahvaljujući svojoj neobaviještenosti. Ova peteročlana obitelj živjela je u jednome kućanstvu čiji je dio namijenjen različitim fazama proizvodnje akumulatora već 14 godina. Akumulatori su se sušili na otvorenome. Na imanju je bio i bunar s pitkom vodom. Mjerenja biopokazatelja izloženosti olovu i njegova djelovanja u svih pet članova obitelji dovela su do alarmantnoga saznanja o razinama olova u krvi [(3,92±0,94) µmol L-1], 50 %-tnom padu aktivnosti dehidrataze δ-aminolevulinske kiseline [(24,67±5,12) U L-1] te povišenom cinkovu protoporfirinu [(1228±480) µg L-1]. Jetrene probe otkrile su povišene razine alkalne fosfataze u serumu [(170,41±41,82) U L-1]. Ostali su parametri jetrene funkcije bili normalni. Testovi funkcije bubrega otkrili su povišene razine mokraćne kiseline u serumu [(515,81±86,29) µmol L-1], dok su razine ureje i kreatinina bile normalne. Također je zabilježen pad razina kalcija u serumu [(1,90±0,42) mmol L-1 u žena te (2,09±0,12) mmol L-1 u muškaraca]. Povišeni krvni tlak zamijećen je u glave obitelji i njegove supruge, dok je u djece bio normalan. Koncentracija olova u bunarskoj vodi bila je izrazito visoka, prema procjeni 180 µg L-1. Obitelj je upućena u indijski Državni referalni centar za otrovanje olovom (National Referral Centre for Lead Poisoning) gdje je primila lijekove i bila upoznata s činjenicama vezanim uz otrovanje olovom. Tromjesečno je praćenje pokazalo blagi pad razina olova u krvi te značajan porast hemoglobina. Ovi se nalazi mogu pripisati promjenama u ponašanju obitelji, bez obzira na to što je nastavila proizvoditi akumulatore

Electrochemical methods for speciation of trace elements in marine waters. Dynamic aspects

The contribution of electrochemical methods to the knowledge of dynamic speciation of toxic trace elements in marine waters is critically reviewed. Due to the importance of dynamic considerations in the interpretation of the electrochemical signal, the principles and recent developments of kinetic features in the interconversion of metal complex species will be presented. As dynamic electrochemical methods, only stripping techniques (anodic stripping voltammetry and stripping chronopotentiometry) will be used because they are the most important for the determination of trace elements. Competitive ligand ex- change-adsorptive cathodic stripping voltammetry, which should be considered an equilibrium technique rather than a dynamic method, will be also discussed because the complexing parameters may be affected by some kinetic limitations if equilibrium before analysis is not attained and/or the flux of the adsorbed complex is in fluenced by the lability of the natural complexes in the water sample. For a correct data interpretation and system characterization the comparison of results obtained from different techniques seems essential in the articulation of a serious discussion of their meaning