Author name:
علياء حسن علـي السماوي
Supervisor name:
كريم ناصر طاهر
Abstract:
اجريت هذه الدراسة في محافظة القادسية للمدة من كانون الاول 2012 لغاية اذار 2013 شملت خمسة مناطق مختلفة من محافظة القادسية هي كل من (مركز الديوانية وناحية السنية وناحية الشافعية وناحية الدغارة وقضاء الحمزة) لغرض تحديد مدى تلوث الحليب الخام ببعض المعادن | This study was carried out in AL - Qadissiyah province during the period from December 2012 to March 2013 involved five different regions such as (Diwaniyah city center , Saniyah district , shafeia district , Dagharah district and AL - Hamza district) to determine the level of contamination of raw milk with the toxic heavy metals such as Cadmium (Cd), Lead (Pb), Nikel (Ni), Arsenic (As) and Mercury (Hg). A total of 150 raw milk samples were collected from 150 animals belonged to three species involved (50) cows , (50) sheep and (50) goats selected randomly, ten animals per each species per regions. The results of a statistical analysis of the experimental data showed that : Chemical components of milk 1.There are a significant differences (p <0.05) in all contents of milk among different species of studied animals (cows , sheep and goats). Except fat content for cows and goats milk were not significant different. Sheep's milk had significantly (p<0.05) of (protein, fat, solids not - fat and ash) in comparison to cow's and goat's milk (7.535, 6.617, 12.026 and 0.646) % respectively. Cow's milk had significantly (p<0.05) higher lactose content (4.757%) than both sheep's and goat's milk. components of milk 2. PhysicalThe results revealed that there were significant differences (p <0.05) in all physical characteristics of milk among different species of animals involved in this study (cows, sheep and goats). Sheep milk had significantly (p<0.05) (Titratable Acidity 0.182% and conductivity 3.214 mS/cm) than both cow's and goat's milk , goat's milk contains the highest specific gravity 1.057mg /100 ml while the pH values of cow's , sheep's and goat's milk were similar. Heavy metals in milk - Effect of Species The results revealed that significant differences (P<0.05) among the mean values of heavy metal concentrations included in the study (Cadmium (Cd) , lead (Pb), Nikel (Ni), Arsenic (As) and Mercury (Hg) in milk of different species (cows , sheep and goats). Sheep's milk had significantly levels of such heavy metals (0.251, 0.801, 0.563, 0.283 and 0.124) mg/ l respectively than both cow's and goat's milk while cow's milk had significantly the lower levels (0.098, 0.311, 0.221, and 0.122 , 0.037) mg / l respectively. - Effect of regions : The results showed that significant differences (P<0.05) in the means values of heavy metal concentrations in milk among different regions. The Highest levels of heavy metals were observed in AL - Hamza district (0.184, 0.624, 0.494, 0.246 and 0.119) mg / l respectively and the lowest levels of heavy metals were noticed in Dagharah (0.144 , 0.507, 0.382 , 0.167 and 0.061) mg / l respectively. - Effect of month : The results of the statistical analysis showed that there were non - significant differences in the average concentrations of cadmium, lead and arsenic among months while a significant differences (P <0.05) were observed in the level of nikel between march and other studied months [(0.494) mg / l in march and (0.397, 0.418 and 0.415) mg / l for December, January and February respectively]. Also the results showed that there were a significant differences (P<0.05) in the levels of mercury between march and each of January and February [(0.106) mg / l in march and (0.081 and 0.083) mg / l in January and February respectively]. From the results obtained in the present study,it can be concluded that : 1 - Heavy metals like cadmium (Cd), lead (Pb), Nikel (Ni), Arsenic (As and Mercury (Hg) which distributed among different sites were exceed the maximum acceptable limits set by WHO and EPA. 2 - High concentration of heavy metals (Cd, Pb, Ni, As and Hg) in city center site may be due to the industrial activities. 3 - High concentration of heavy metals in the other sites may be due to application of waste water for agriculture purposes (irrigation) which pollute the soil and also be allowing toxic metals to enter in to the food chain posing a serious health hazard.
