Confirmatory Analysis of Per and Polyfluoroalkyl Substances in Milk and Infant Formula Using UHPLC–MS/MS

An ultra-high performance liquid chromatography tandem mass spectrometry method was developed and validated for the sensitive determination and unambiguous confirmation of residues of per and polyfluorinated alkyl substances (PFAS) in breastmilk, retail milk and infant formulas following two sample preparation methods. Sample pre-treatment was carried out by a simplified QuEChERS method without requiring dSPE or any further clean-up. The method was validated in accordance with the requirements of Commission Decision 657/2002/EC with slight modifications. The method displayed good linearity with R(2) ranging from 0.9843–0.9998 for all target PFAS. The recovery and within-laboratory reproducibility of the method (n = 63) were in the range 60–121% and 5–28%, respectively. The decision limit, detection capability and limit of quantitation ranged from 30–60 ng kg(−1) to 40–100 ng kg(−1) and 5–50 ng kg(−1), respectively. Acceptable matrix effect values in the range −45–29% were obtained with uncertainty of measurement lower than 25% for all target PFAS. The method displays its suitability for the sensitive and high-throughput confirmatory analysis of C(4)–C(14) PFAS in breastmilk, dairy milk and infant formulas

An ethnobotanical survey of medicinal plants used by traditional healers for the treatment of cancer in Hammanskraal and Winterveld, Tshwane Metropolitan Municipality, South Africa

Background: Knowledge of medicinal plants used by the traditional healers are mostly confined among the locals and the adherents, hence, proper enquiry and documentation can help the ever dynamic scientific world to find permanent cure to the menace of such deadly diseases such as cancer. This study aimed at (1) specifically recording medicinal plants traditionally used for the treatment of cancer in Hammanskraal and Winterveld, South Africa, and (2) documenting the different methods of preparation and administration of those medicinal plants as recorded during the study. Method: An open-ended semi-structured questionnaire was administered to 90 willing traditional healers in Hammanskraal and Winterveld area, Tshwane Municipality, South Africa to document plants used for cancer treatments. The study was conducted over a period of six months (July – December, 2018). Descriptive statistics was used to present the obtained data. Results: The study recorded twenty-eight plant species belonging to 18 families for the treatment of different types of cancer. Plant species in the Fabaceae family particularly Lessertia frutescens (L.) Goldblatt and J.C. Manning, Senna italica Mill and Trifolium pratense L. were the most prominently mentioned (highest citation frequency) by the traditional healers for lung, and skin cancer treatment. Based on the citation frequency, the most treated cancer by the traditional healers is in the order: skin cancer > lung cancer > breast cancer > prostate cancer > cervical cancer. The method of preparation included decoction(32.3%), infusion (29%), paste (16.1%) and maceration (22.6%). Conclusion: In addition to the documentation of indigenous knowledge related to the use of medicinal plants in the traditional management of cancer in South Africa, this study opens a vista for investigations into the phytochemical and pharmacological properties of the documented plants. Keywords: Cancer; Indigenous plants; Medicinal plants; South Africa; Traditional practitioners

Urban farming as a possible source of trace metals in human diets

Rapid industrialisation and urbanisation have greatly increased the concentrations of trace metals as pollutants in the urban environment. These pollutants (trace metals) are more likely to have an adverse effect on peri-urban agriculture which is now becoming a permanent feature of the landscape of many urban cities in the world. This review reports on the concentrations of trace metals in crops, including leafy vegetables harvested from different urban areas, thus highlighting the presence of trace metals in leafy vegetables. Various pathways of uptake of trace metals by leafy vegetables, such as the foliar and roots, and possible health risks associated with urban faming are discussed and various morphological and physiological impacts of trace metals in leafy vegetables are described. Defensive mechanisms and positive aspects of trace metals in plants are also highlighted

Urban farming as a possible source of trace metals in human diets

Rapid industrialisation and urbanisation have greatly increased the concentrations of trace metals as pollutants in the urban environment. These pollutants (trace metals) are more likely to have an adverse effect on peri-urban agriculture which is now becoming a permanent feature of the landscape of many urban cities in the world. This review reports on the concentrations of trace metals in crops, including leafy vegetables harvested from different urban areas, thus highlighting the presence of trace metals in leafy vegetables. Various pathways of uptake of trace metals by leafy vegetables, such as the foliar and roots, and possible health risks associated with urban faming are discussed and various morphological and physiological impacts of trace metals in leafy vegetables are described. Defensive mechanisms and positive aspects of trace metals in plants are also highlighted

Efficient Micropropagation Protocol for the Conservation of the Endangered Aloe peglerae, an Ornamental and Medicinal Species

A number of Aloe species are facing an extremely high risk of extinction due to habitat loss and over-exploitation for medicinal and ornamental trade. The last global assessment of Aloe peglerae Schönland (in 2003) ranked its global conservation status as ‘endangered’ with a decreasing population trend. In the National Red List of South African Plants, the extremely rapid decline of this species has resulted in its conservation status being elevated from ‘endangered’ to ‘critically endangered’ based on recent or new field information. This dramatic decline necessitates the development of a simple, rapid and efficient micropropagation protocol as a conservation measure. An in vitro propagation protocol was therefore established with the regeneration of 12 shoots per shoot-tip explant within 8 weeks using Murashige and Skoog (MS) medium supplemented with 2.5 µM meta-topolin riboside (an aromatic cytokinin). The rooting of the shoots with a 100% frequency on half-strength MS medium without any plant growth resulted in additional six shoots produced per cultured shoot. The resultant plantlets were successfully acclimatized with a 100% survival frequency after 6 weeks. Overall, the developed protocol can result in the production of 3906 transplantable shoots that are ready for rooting per annum from a single shoot-tip explant. It is simple and efficient for seedling production in the ex situ cultivation and conservation of the endangered A. peglerae

Health Risk Assessments of Selected Trace Elements and Factors Associated with Their Levels in Human Breast Milk from Pretoria, South Africa

While breast milk is the recommended food for infants up to at least six months, exogenously derived compounds such as trace elements have been widely reported in human milk which may make it become toxic or a source of pollutants to the infants. Numerous short- and long-term health effects have been associated with high body—burdens of trace elements, which are amplified in infants. The current study determined the levels and possible contributing factors of six trace elements in breast milk of nursing mothers from a local hospital in Pretoria. Extraction of trace elements employed a digestion technique using perchloric and nitric acid in a ratio of 1:3, while Inductively Coupled Plasma–Membrane Spectrophotometry was used to identify and quantify their levels in breast milk. Concentrations of Cr and Mn were the highest in breast milk, with values ranging from 0.30 to 5.72 µg/L and 0.23 to 5.13 µg/L, respectively. Levels of Co, As, Pb and Cd ranged from <LOD to 0.2 µg/L, <LOD to 2.29 µg/L, 0.05 to 1.06 µg/L, and 0.004 to 0.005 µg/L, respectively. Levels of Cr, Mn and As were higher than the recommended limits from WHO (World Health Organization) in some milk samples. Dietary assessments showed minimal risk for the infants through breastfeeding at this stage; however, prolonged exposure to other sources of these toxic trace elements may pose a serious health risk for the infants. The nature of employment, infant birth weight, passive smoking and maternal diet were the significant factors noted to contribute to trace metal levels in breast milk

Concentrations of Pb and Other Associated Elements in Soil Dust 15 Years after the Introduction of Unleaded Fuel and the Human Health Implications in Pretoria, South Africa

Leaded fuel has been reported to contain certain amounts of toxic trace metals such as Pb and Cadmium (Cd), which may have negative impacts on humans and the environment. Unleaded fuel was introduced to South Africa in 2006 with the aim of reducing and eventually eliminating the negative impact of leaded fuel on the environment. However, trace metals are usually nonbiodegradable, and it may therefore be necessary to monitor their presence in the environment so as to evaluate their possible impact on human health. The present study evaluated the levels of Pb and other heavy metals in soil samples collected from petrol (gas) filling stations and from busy roads just around the filling stations in Pretoria, South Africa, fifteen years after the introduction of unleaded fuel. A total of twenty-four (24) soil samples were analysed for lead (Pb), chromium (Cr), copper (Cu), zinc (Zn), arsenic (As), iron (Fe), manganese (Mn), nickel (Ni), titanium (Ti), and cadmium (Cd) using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results showed that the concentrations of the trace metals were in the following ranges: Pb, 0.08 ± 0.02–188.36 ± 15.32 ug/g; Mn, 5.35 ± 0.34–6842.43 ± 1.35 ug/g; Zn, 1.82 ± 0.22–9814.89 ± 22.32 ug/g; As, 0.21 ± 0.00–8.42 ± 2.44 ug/g; Cu, 10.51 ± 3.41–859 ± 0.09 ug/g; Cr, 5.80 ± 2.21–417.70 ± 9.08 ug/g; Ti, 19.94 ± 4.99–1036.12 ± 1.49 ug/g; and Fe, 3.06 ± 7.87–674.07 ± 12.22 mg/g. The highest concentrations from all the elements were recorded for Fe in all the collected soil samples. The concentrations of Pb in the soils collected from sites associated with high traffic and industrial areas were higher than for those from all other sites, and the differences were significant (p < 0.05). The pollution index (PI), which is the anthropogenic influence of the trace metals, and the geoaccumulation (Igeo), which allows for the removal of possible variations as regards the studied element in the soil due to the possible differences in the background value, showed that some samples were enriched anthropogenically. The PI for Ni, Pb, Cu, and Cr indicated highly anthropogenically contaminated soils, especially at sites associated with high traffic volumes and in industrial areas. The Igeo showed moderately polluted areas for Pb and Cu in high-traffic areas. The exposure routes for the toxic trace metals that were of concern in the study were either through ingestion or dermal contact. The calculated hazard quotient showed both noncarcinogenic and carcinogenic risks for Fe and Mn via ingestion and through dermal contact for both children and adults, respectively. The concentrations of Pb were high and similar to those that were previously reported in the study and pointed to vehicular emission as one of the contributors. The study also noticed an increase in the presence of Mn and Fe in all soil samples