Application of Bentonite Clay, Date Pit, and Chitosan Nanoparticles as Promising Adsorbents to Sequester Toxic Lead and Cadmium from Milk

Evaluating residual lead (Pb) and cadmium (Cd) levels in food products, especially milk, is critical for product safety and quality. In this purview, the current study aims to determine Pb and Cd concentrations in milk using atomic absorption spectrophotometry and compare their values with international standards. In addition, it aims to remove these metals from milk samples using low-cost, naturally occurring materials, such as bentonite, date pit, and chitosan nanoparticles. The ability of potential adsorbents was also investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscope (TEM). Moreover, their impact on milk's nutritional properties was considered. The results revealed that most milk samples contained Pb and Cd, with mean values of 0.237 ± 0.179 and 0.041 ± 0.036 mg/kg, respectively. Furthermore, the three possible adsorbents demonstrated high sequestering ability due to their existing functional groups; the adsorption capacity of bentonite to Pb and Cd was 84 and 88%, date pit was 97 and 93%, and chitosan nanoparticles were 82 and 98%, respectively, with no discernible change in milk nutritional contents. In conclusion, the bentonite, date pit, and chitosan nanoparticles were found to be significantly effective and safe in removing hazardous trace elements (Pb and Cd) from contaminated milk.

The efficacy of clay bentonite, date pit, and chitosan nanoparticles in the detoxification of aflatoxin M1 and ochratoxin A from milk

Aflatoxin M₁ (AFM₁) and ochratoxin A (OTA) are highly toxic mycotoxin metabolites that are found as food pollutants, posing health risks to humans and animals. The objective of the current study is to establish a sensitive, reliable method for determining AFM₁ and OTA using high-performance liquid chromatography (HPLC) and attempting to assess the efficacy of bentonite, date pit, and chitosan nanoparticles for AFM₁ and OTA detoxification from contaminated milk. As revealed, AFM₁ was found in 65.7% of analyzed samples ranging from 4.5 to 502 ng/L, while 25.7% of examined samples contained OTA ranging from 1.45 to 301 ng/L. Furthermore, for AFM₁ and OTA. The advanced procedure was thoroughly validated by evaluating linearity (R² > 0.999), LOD (0.9615 and 0.654 ng/L), and LOQ (2.8846 and 1.963 ng/L), recovery (93-95% and 87-91%), as well as precision (≤ 1%RSD). The experimental data revealed a higher removal efficiency of bentonite and date pit than chitosan nanoparticles in the case of AFM₁ (68%, 56%, and 12%) and OTA (64%, 52%, and 10%), respectively with slight change in nutritional milk components like fat, protein, and lactose. Eventually, it is concluded that bentonite and date pit can be considered efficient adsorbing agents to extract AFM₁ and OTA from contaminated milk.