Lead concentrations in breast milk of Moroccan nursing mothers and associated factors of exposure: CONTAMILK STUDY

High lead contamination in Mother's breastmilk in Bihar (India): Health risk assessment of the feeding children

Lead poisoning in the recent times has caused serious health threats in the exposed human population. It is estimated that about 815 million people are exposed to lead poisoning worldwide and in India total 275 million children are exposed to blood lead contamination. The present study was carried outed in 6 districts of Bihar to know the extent of lead exposure in the children through their mother's breastmilk. The biological samples such as breastmilk, mother's urine, child's urine, and mother's blood samples were collected for quantitative lead estimation. Moreover, the selected household water sources (handpump) and the food consumed by the individuals-wheat, rice and potato samples were also collected for lead quantification. The study reveals that the breastmilk had high lead content in 92% of the samples (highest value 1309 μg/L), in blood presence of lead was observed in 87% studied samples (highest value 677.2 μg/L). In mother's urine the highest lead value was 4168 μg/L (62%) and in child's urine the highest value was 875.4 μg/L (62%) respectively of the studied samples. Moreover, in the studied food samples, wheat had lead content in 45% the studied samples (highest value 7910 μg/kg). In rice in 40% of the studied samples (highest value 6972 μg/kg) and in potato 90% of the studied samples (highest value = 13786 μg/kg) were found with elevated lead content respectively. The hazard quotient (HQ) and the cancer risk (CR) for lead contamination was very much higher in mothers followed by their children. The entire study indicated that lead exposure through food (wheat, rice and potato) has reached the mother's breastmilk and from their it has reached their child's body. This could cause serious hazards in the exposed children causing serious neurological damages, low IQ, low memory, and low mental growth in them. Therefore, a strategic action is required to control the present problem.

Assessment of Heavy Metals and Trace Elements in the Human Milk of Women Living in Latvia and an Evaluation of Influencing Factors

During lactation, heavy metals and trace elements can be mobilised from the maternal body stores and excreted via human milk. A total of 66 mature human milk samples were collected from lactating women in Latvia between 2016 and 2017 to analyse the content of As, Cd, Pb, Al, Sn, and Ni. Additionally, 50 mature human milk samples were collected between 2022 and 2023 to analyse the content of Cd and Pb. The content of heavy metals and trace elements in human milk was determined using ICP-MS. Only two individual human milk samples contained heavy metals above the method's detection limit-one with an arsenic content of 0.009 mg kg-1 and one with a lead content of 0.047 mg kg-1. The preliminary data show that human milk among lactating women in Latvia contains only insignificant amounts of heavy metals and trace elements. Concern over such content should not be a reason to choose formula feeding over breastfeeding. Nevertheless, heavy metals, trace elements and other pollutants in human milk should be continuously monitored.

Lactational Exposure of Human Infants to Metal (loid)s: A Comparison of Industrial and Urban Inhabitants in North of the Persian Gulf

In this study, postnatal metal (loid)s (MLs) exposure was compared between the petrochemical and gas area of Asaluyeh (PGA) and urban area of Kaki (UA) in Bushehr province, Iran. Two hundred human breast milk (BM) samples from the industrial and urban areas were analyzed for MLs using Inductivity Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Boron (B), copper (Cu), iron (Fe), and nickel (Ni) were found at the highest levels in both study areas. Adjusted multiple linear regression models revealed that the mean concentration of total MLs in BM samples collected from the PGA was statistically significantly greater than that of the UA (655.85 vs. 338.17 µg/L). Also, the mean concentrations of all detected MLs in BM samples collected from the PGA were statistically significantly higher than those collected from the UA. The hazard index (HI) of combined MLs in the PGA and UA illustrated non-cancer risk for infants. Lead (Pb) and chromium (Cr) in the PGA and Cr in the UA showed the risk of cancer. So it can be concluded that nursing infants from an industrial area are most at risk for MLs exposure during entire lactation course than those from an urban area.

Essential and non-essential element concentrations in human milk samples and the assessment of infants' exposure

As the data concerning element concentrations in human milk (HM) samples and their intake by infants are lacking in Poland, the present study aimed to explore this issue. The material consisted of HM samples obtained from 30 exclusively breastfeeding mothers during 4-6 weeks postpartum. Additionally, to identify the factors that may potentially affect HM composition, information regarding maternal data (anthropometry, body composition, and diet) was also collected. Maternal diet was assessed with two methods-a food frequency questionnaire and 3-day dietary records. In total, 18 essential and non-essential elements were determined. For the elements analysis, we used inductively coupled plasma quadrupole mass spectrometry. Most of the elements (n = 11, 61%) were detected in all HM samples. In all HM samples tin concentration was higher (5.67 ± 2.39 μg/L) than the usual range reported by the World Health Organization (~ 1.0 μg/L). HM cadmium content was positively associated with maternal salty snacks intake (r = 0.502, p = 0.005), arsenic with whole-grain products intake (r = 0.37, p = 0.043), and mercury concentration with fruits and seeds/nuts consumption (r = 0.424, p = 0.042 and r = 0.378, p = 0.039, respectively). Higher HM lead concentration was predicted by maternal age (95% CI [0.94-0.97]), intake of fish (95% CI [1.01-1.03]), and vegetables (95% CI [1.02-1.06]). The highest infants' intake was observed for copper (35.24 ± 12.48) and the lowest for arsenic (0.076 ± 0.102). Infants' exposure to lead was associated with maternal frequency consumption of canned fish (p = 0.0045). There is a need to perform further research on this topic to maximize the benefits of breastfeeding by minimizing maternal and infant exposure to potentially toxic elements.

Subacute Exposure to Low Pb Doses Promotes Oxidative Stress in the Kidneys and Copper Disturbances in the Liver of Male Rats

Recent data indicate that lead (Pb) can induce adverse effects even at low exposure levels. Moreover, the corresponding mechanisms of low Pb toxicity have not been well identified. In the liver and the kidneys, Pb was found to induce various toxic mechanisms leading to organ physiological disruption. Therefore, the purpose of the study was to simulate low-dose Pb exposure in an animal model with the aim of assessing oxidative status and essential element levels as the main mechanism of Pb toxicity in the liver and kidneys. Furthermore, dose-response modelling was performed in order to determine the benchmark dose (BMD). Forty-two male Wistar rats were divided into seven groups: one control group, and six groups treated for 28 days with 0.1, 0.5, 1, 3, 7, and 15 mg Pb/kg b.w./day, respectively. Oxidative status parameters (superoxide dismutase activity (SOD), superoxide anion radical (O₂^-), malondialdehyde (MDA), total sulfhydryl groups (SHG), and advanced oxidation protein products (AOPP)) and Pb, copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) levels were measured. Lowering Cu levels (BMD: 2.7 ng/kg b.w./day), raising AOPP levels (BMD: 0.25 µg/kg b.w./day) in the liver, and inhibiting SOD (BMD: 1.3 ng/kg b.w./day) in the kidneys appear to be the main mechanisms of Pb toxicity. The lowest BMD was derived for a decrease in Cu levels in liver, indicating that this effect is the most sensitive.

Toxic metal and trace element status in the breast milk of Turkish new-born mothers

BACKGROUND AND AIM

This study aims to evaluate the toxic metal and trace element concentrations in breast milk obtained from new-born nursing mothers in rural Giresun province, located on the coast of the Black Sea.

METHODS

Milk samples were randomly collected once from early lactation of 50 nursing mothers. Inductively coupled plasma mass spectrometry was used to analyse the concentrations of iron (Fe), nickel (Ni), manganese (Mn), cobalt (Co), chromium (Cr), copper (Cu), zinc (Zn), arsenic (As), molybdenum (Mo), cadmium (Cd) and lead (Pb) in the breast milk. Shapiro-Wilk test was used to evaluate the distribution of data. The Pearson-J correlation was used for normally distributed elements, and Spearman correlation analysis was used for others.

RESULTS

The mean amounts of elements were 3.36 µg kg^-1 of Cr, 9.26 µg kg^-1 of Mn, 797 µg kg^-1 of Fe, 1.99 µg kg^-1 of Ni, 5.92 µg kg^-1 of Cu, 379 µg kg^-1 of Zn and 2.23 µg kg^-1 of Pb. Co, As, Mo and Cd concentrations were below the detection limit. A highly significant correlation was found between iron and Nickel in breast milk.

CONCLUSION

Our findings were evaluated in comparison with the WHO data, and whether they were in accordance with the recommended Dietary Reference Intake (DRI) values for 0-6-months-old infants was calculated. Pb levels were similar to those of WHO, while As and Cd were below the measurable limit. Fe, Mn, and Cr concentrations were higher than WHO data, while Co, Ni, Cu and Zn were lower. This research is the first study conducted in this region.

Levels of mercury in Moroccan breast milk and the affecting factors: CONTAMILK study

This study aims to evaluate the level of mercury in the breast milk of Moroccan mothers and its association with several maternal parameters and habits, and to estimate the daily intake of the newborns. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of mercury in 70 colostrum samples. Indeed, a structured questionnaire was administrated during milk collection to report data concerning the maternal socioeconomic and anthropometric parameters, as well as dietary habits and smoking habits in the family, etc. The median of mercury in breast milk was 3,56 μg/L (range 1.64-124 μg/L) and exceeded normal levels of 1.7 μg/l, suggested by the World health organization in 99% of milk samples. Significant associations were found between mercury levels and the occurrence of previous miscarriages, anemia before pregnancy and vitamin & mineral supplementation during pregnancy, as well the frequency of consumption of cereals and the use of lipstick. The estimated daily intake was higher than the tolerable daily intake of the World health organization and the European food safety authority in 30% of newborns. These results need to be confirmed by multicenter studies to investigate the levels of mercury in the breast milk of the Moroccan population.