Untitled - MendelNet 2013 - Mendelova zemědělská a lesnická ...

MENDELNET 2013concentrations of DBP ranged from 2.76 ± 1.20 mg.kg -1 and 7.02 ± 4.26 mg.kg -1 and DEHP from0.01 ± 0.01 mg. kg -1 to 0.06 ± 0.06 mg.kg -1 .Statistically strongly significantly lower (p < 0.01) average concentrations of DBP and DEHP werefound in samples of milk obtained by hand milking.Statistically highly significant difference (p < 0.01) between average concentrations of DBP orDEHP for individual cows in a single method of milking was found.Yong-Lai et al. (2005) found that phthalic acid esters released from PVC hoses used for milkingcould be a source of potential contamination of milk and milk products. As in the study by Fierenset al. (2012) a lower average concentration of contamination of milk samples milked by hand(100 μg.kg -1 fat) compared to samples milked by a machine (179 μg.kg -1 fat) were revealed, it wasconcluded that milking devices are an important source of milk contamination. These findings cansupport the results obtained in our experiment, since statistically strongly significantly lower(p < 0.01) average concentrations of DBP and DEHP were found in milk samples milked by hand.Differences in accumulation of DEHP and DBP in cow milk may be caused by differentmetabolism of cows, ratio between accumulation and elimination of phthalates from the body andpartially by different physico-chemical properties of both phthalates. DBP has a smaller moleculewith a shorter unbranched chain allowing partial solubility of DBP in water. DEHP is insoluble inwater.Rhind et al. (2005) reported that, due to the lipophilic nature of phthalates, their accumulation fromthe feed and environment in animal tissues, muscle, fat can occur and also phthalates may passfrom the digestive tract to the milk, which leads to another potential threat of the food chain andthereby to humans.CONCLUSIONSCurrently effective legislation in the Czech Republic does not cover the issue of phthalates infoodstuffs. Under the Act No. 110/1997 Coll., on Foodstuffs and Tobacco Products, and DecreeNo. 53/2002 Coll., phthalates content was regulated by determining the permissible amount of thesum of DEHP and DBP. Allowable amounts of these phtalates in spirits were determined in theamount of 1 mg.kg -1 , in child and infant nutrition, and in the so-called basic foodstuffs, in muscle oflivestock in the amount of 2 mg.kg -1 of the original sample and in fat 4 mg.kg -1 . However, byadoption of EU legislation in 2004 these limits were omitted from the Decree. Nevertheless,assuming the validity of these limits, all analyzed milk samples regardless of the date and type ofmilking were found to be unsuitable.Therefore, these compounds ought to be monitored. Necessity of potential provisions on thelegislative limits for phthalates in feed should be considered in order to prevent potentialcontamination of the food chain.One way to gradually reduce the risks of phthalates is to promote the substitution of toxicphthalates by other health-harmless substances such as citrates, phenol alkyl sulfonates, benzoates,especially in the production of materials used in agriculture, food industry, and health care.595 | P age