Osman SÖNMEZ, Salih AYDEMİR, Ebru SAYGAN

Kurşun ve kurşun biyo-alınabilirliğinin belirlenmesi

Kurşun hayvanlar, insanlar ve özelliklede küçük çocuklar için zehirlidir. Kurşun ve kurşun bileşikleri çevreye o kadar dağılmıştır ki, bu element günümüzde çevre kirletici olarak büyük kaygı uyandırmaktadır. İnsanlar, topraktan toksik metalleri iki farklı yolla vücutlarına almaktadır; bunlardan birincisi toprak yemek suretiyle (özellikle küçük çocuklar arasında yaygın) veya toz şeklinde burundan solunum yoluyla girmekte ve ikincisi ise gıda zinciri yoluyla vücuda girmektedir. Bunlar arasında kurşunun vücuda alınış yolu olarak en önemlisi ağız ve burundan olanıdır. Kurşun biyo-alınabilirliğinin in vitro ve in vivo gibi çeşitli metodlardan biriyle belirlenebilmektedir. Yerinde (in situ) kurşun stabilizasyonu gelecek vadeden bir method olmaktadır. Kurşunun biyo- alınabilirliğinin azaltılması kurşun fosfatlar gibi çözünmeyen bileşiklerinin oluşturulması veya kurşunun Mn oksitler gibi güçlü adsorbe ediciler üzerine adsorbsiyonunun sağlanması veya her iki yöntemin birlikte kullanılması suretiyle başarılabilir.

Lead and determination of lead bioavailability

Lead (Pb) is toxic to animals and humans especially to young children. As Pb and its compounds can be found in all parts of the environment, there is considerable concern regarding this element as a contaminant in the environment. Although humans may assimilate soil toxic metals through two major patways: soil ingestion and through the food chain, soil ingestion by hümans is one of the major exposure patways of concern. Soil Pb bioavailability can be estimated by one of several methods. These are in vivo and in vitro studies. İn situ stabilization of lead is becoming a promising idea. Soil Pb bioavailability can be decreased by either forming insoluble Pb compounds like pyromorphites or adsorption of Pb on strong adsorbents like Mn oxides or both simultaneously.

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