Transgenerational Effects of Heavy Metal Pollution on Immune Defense of the Blow Fly Protophormia terraenovae

Recently environmental conditions during early parental development have been found to have transgenerational effects on immunity and other condition-dependent traits. However, potential transgenerational effects of heavy metal pollution have not previously been studied. Here we show that direct exposure to heavy metal (copper) upregulates the immune system of the blow fly, Protophormia terraenovae, reared in copper contaminated food. In the second experiment, to test transgenerational effects of heavy metal, the parental generation of the P. terraenovae was reared in food supplemented with copper, and the immunocompetence of their offspring, reared on uncontaminated food, was measured. Copper concentration used in this study was, in the preliminary test, found to have no effect on mortality of the flies. Immunity was tested on the imago stage by measuring encapsulation response against an artificial antigen, nylon monofilament. We found that exposure to copper during the parental development stages through the larval diet resulted in immune responses that were still apparent in the next generation that was not exposed to the heavy metal. We found that individuals reared on copper-contaminated food developed more slowly compared with those reared on uncontaminated food. The treatment groups did not differ in their dry body mass. However, parental exposure to copper did not have an effect on the development time or body mass of their offspring. Our study suggests that heavy metal pollution has positive feedback effect on encapsulation response through generations which multiplies the harmful effects of heavy metal pollution in following generations

Development and validation of an analytical method for arsenic in urine

The development and validation of a method for analyzing arsenic in urine samples of non specific exposed persons has been described. Measurements are performed by FIA-AAS based on reduction of inorganic arsenic to arsine. In this way only inorganic arsenic can be quantified. For total arsenic determination in urine a digestion must be performed in order to convert organic-bound arsenic into its inorganic form. A method of UV-photodestruction is optimised followed by establishing the performance characteristics of the entire procedure. The limit of detection is found to be 0.35 mug/l urine, repeatability and within lab reproducibility are better than 5% and 8 % respectively (calculated as relative standard deviation) for arsenic concentrations above 3 mug/l. The method is also validated with certified reference materials of human urine. Results obtained were well within the certified intervals. Several urine samples analysed with the developed method were also analysed with HPLC / ICP-MS to check results. Arsenic concentrations in the urine samples did not differ from each other significantly.Beschreven is het onderzoek voor het ontwikkelen en valideren van een gevoelige analyse- methode voor de bepaling van het totaal arseengehalte in urine van niet specifiek blootgestelde personen. De metingen zijn verricht met hydride FIA-AAS gebaseerd op vorming van arseenhydrides. Daar alleen anorganisch arseen middels deze techniek gemeten kan worden is een geschikte monstervoorbewerkingsstap nodig voor de omzetting van organisch gebonden arseen in anorganisch arseen. Een UV-destructiemethode is geoptimaliseerd waarna de prestatiekenmerken van de gehele procedure zijn vastgesteld. De aantoonbaarheidsgrens is bepaald op 0,35 mug/l urine terwijl de herhaalbaarheid en de binnenlaboratorium reproduceerbaarheid voor arseengehalten van meer dan 3 mug/l beter is dan respectievelijk 5% en 8% uitgedrukt als relatieve standaarddeviatie. De methode is tevens gevalideerd met gecertificeerde referentiematrialen humane urine. De gemeten resultaten lagen ruim binnen de gecertificeerde intervallen. Naast de analyse van diverse monsters urine met de ontwikkelde methode zijn dezelfde monsters ter controle onderzocht met HPLC / ICP-MS. De arseengehalten gemeten met elk van de methoden verschillen niet significant van elkaar