Heavy metals in cow’s milk and cheese produced in areas irrigated with waste water in Puebla, Mexico

Abstract

The aim of this work was to determine Ni, Cr, Cu, Zn, Pb, and As levels in raw milk and Oaxaca and ranchero type cheeses, produced in areas irrigated with waste water from Puebla in Mexico. Milk results showed a mean Pb level of 0.03 mg kg, which is above the maximum limit as set by Codex Alimentarius and the European Commission standards. For As a mean value of 0.12 mg kg in milk was obtained. Mean As and Pb levels in milk were below the Mexican standard. Milk whey and ranchero cheese had mean Pb levels of 0.07 and 0.11 mg kg, respectively. As was higher in Oaxaca and ranchero cheese at 0.17 and 0.16 mg kg, respectively. It was concluded that cheeses made from cow's milk from areas irrigated with waste water are contaminated with Pb and As, which may represent a health risk.

Determination of the content of Pb, Cd, Cu, Zn in dairy products from various regions of Poland

“…The study by Kulek de Andrade et al [31] also showed that the content of lead in yoghurt can depend on production process because samples of a drinkable yoghurt contained a higher amount of this element than a pasty one. The concentration of lead in curd and cheese reported by Castro-Gonzalez et al [28] was comparable to or higher than in milk. The authors concluded that it was due to increasing the protein content (lead has an affinity for protein) and decreasing the moisture level during cheese production.…”

“…In other European countries the Pb content in milk (mg/kg) was as follows: Slovenia -0.05 and Spain -0.0018 [22], Austria -0.0065 [23], Italy -0.0013 [24] and Romania -from 0.052 to 0.617 mg/kg [25]. Mean lead content in milk from Turkey was 0.0335 mg/kg [26], from Iran -0.0129 mg/kg [27], from Mexico -0.03 mg/kg [28] and from Pakistan -from 0.001 to 1.428 mg/l [29]. The results of Pb content determination in yoghurt reported by Khan et al [30] indicated that this product may contain a much higher concentration of this toxic element (4.21 -24.50 ng/g) than milk (3.35 ng/g).…”

Trace and rare earth elements determination in milk whey from the Veneto region, Italy

“…The zinc content in goat milk whey samples from AZ have mean concentrations (0.025 mg kg − 1 ) 50 times less than the only other published goat milk whey value of (1.20 mg kg − 1 ) (Herrera García et al, 2006). The mean Zn values in cow milk whey (0.166, 0.088, and 0.100 mg kg − 1 , from LB1, LB2, and LB3, respectively) are similar to the values of 0.23 and 0.13 mg kg − 1 from other studies (Castro-González et al, 2018;Reykdal et al, 2011). However, all of these results are approximately 10 times less than values (1.2 and 2.2 mg kg − 1 ) obtained by Yüzbaşi et al (2009).…”

“…Our work is also the first to determine Cu concentrations in goat milk whey, with mean concentrations of 0.023 mg kg − 1 . Mean Cu concentrations in cow milk whey (0.024, 0.17, and 0.26 mg kg − 1 , in LB1, LB2 and LB3, respectively) are higher than the results reported in most other cow milk whey studies (Table 3), with the exception of the cow milk whey Cu concentrations of 0.05 mg kg − 1 reported by Castro-González et al (2018). The Cu concentrations in both LB2 and LB3 were about ten times higher than the values reported for AZ and LB1, where these two locations have almost equivalent concentrations.…”

Toxicity in Goats Exposed to Arsenic in the Region Lagunera, Northern Mexico

“…Treatment groups 1 and 3 also presented behavioral changes, hair loss, and keratosis on the nose and mouth. Some studies refer to the epidemiological significance of arsenic exposure via the water consumed by goats, cows and other species [30,31], highlighting the transmission of this metalloid to humans in high value food products derived from these livestock species, with some of the products described as having high arsenic concentrations including milk, meat, and cheese [32][33][34][35][36]. Moreover, products manufactured from goat and sheep milk, such as yogurt, have be shown to contain metals such as arsenic [37].…”