Solar Ultraviolet Radiation Exposure and Sun Protection Behaviors and Knowledge Among a High‐Risk and Overlooked Group of Outdoor Workers in South Africa

The exposure of outdoor car guards to solar ultraviolet radiation (UVR), the majority with deeply pigmented skin, to solar UVR was measured for five consecutive days during early spring (September 2017) in South Africa using electronic UVR dosimeters attached to the upper arm of each participant. The exposure of the nape of the neck, forehead, nose, cheek and hand was extrapolated from the measurements. The onsite ambient solar UVR on a flat, horizontal, unshaded surface was measured concurrently. The sun‐related knowledge, behavior and attitudes of the car guards were evaluated using questionnaires. Total personal daily solar UVR exposure as a percentage of the ambient solar UVR exposure was 24%. The exposure of car guards on several body sites was in excess of the occupational threshold limit value. Sleeved shirts and hats were the most commonly used sun protection measures (worn by 70% and 80%, respectively). Considering the high levels of solar UVR reported on most days throughout the year in South Africa, more studies quantifying the personal exposure of outdoor workers in both the informal and formal sectors are necessary.     

Skin Cancer Awareness Among 1 271 Black Africans in South Africa

Little is known about levels of awareness and perceptions of skin cancer among Africans living in Africa. This study assessed skin cancer awareness among 1271 deeply pigmented South Africans. Participants (n = 642 males vs n = 629 females) were aware of skin cancer (79%) with more females than males being aware of skin cancer (P = 0.02). Majority of all participants had never checked their skin for signs or symptoms of skin cancer (90%). Palms of hands and soles of feet were the least recognized anatomic sites for skin cancer development, despite these sites being the common sites for acral lentiginous melanoma in individuals with deeply pigmented skin. Results suggest a need for targeted skin cancer awareness among population groups with dark skin on identification, screening, and early detection, professional training for healthcare personnel and content on skin cancer in deeply pigmented skin in medical curricula.     

Serum Levels of 25‐Hydroxy‐Vitamin D3 Among Sun‐protected Outdoor Workers in Israel

The objective of this study was to evaluate the effect of reduced sun exposure of outdoor workers on vitamin D status using different modalities of sun protection, for primary prevention of skin cancer. 25‐OH‐D3 measurements were performed in two successive winters, 8 (interim) and 20 months after initiation of the study, in three groups of male outdoor workers, enrolled in either a complete, partial or minimal sun protection program. Ambient solar UVB radiation was monitored simultaneously. No intragroup or intergroup differences were observed between the interim‐ and postintervention measurements of mean 25‐OH‐D3, which were close to 30 ng mL^?1. Significant risk factors for postintervention 25‐OH‐D3 levels >33.8 ng mL^?1 (a surrogate for reduced sun protection) were: previous sunburn episodes (OR 2.5; 95% CI 1.01–6.3; P = 0.05) and younger age (OR 0.92; 95 CI 0.86–0.98; P = 0.009). Outdoor workers of Western, compared with those of Eastern paternal origin had a borderline significant risk (OR 2.4; 95% CI 0.9–6.3; P = 0.07). A borderline significant effect (OR 2.9; 95% CI 0.97–10.1; P = 0.085) was also noted for those in the minimal intervention group. In conclusion, sun protection among outdoor workers following a successful intervention did not suppress mean winter 25‐OH‐D3.     

Nuclear science education and training in South Africa

The role played by national institutes and universities in the education, training and research in South Africa, is described. In addition, details are given of the nuclear science courses available at technikons for students in chemistry, physics, nuclear technology, and analytical and medical applications.     

Fall out and radionuclide analysis on the Pratas Island in South China Sea

The radionuclide concentration in environmental samples and radiation level on Pratas Island are measured prior to the commercial operation of Da-Ya Bay Nuclear Power Plant nearby. Except for some minute amount of⁶⁰Co and¹⁵⁷Cs, radiation background is mainly from naturally occurring radionuclides. Automatic radiation surveillance and a routine sampling program on Pratas Island are essential to provide early warning for Taiwan in case of nuclear emergency.     

Ultraviolet radiation exposure of children and adolescents in Durban,South Africa

The solar ultraviolet radiation (UVR) exposure of 30 children and adolescents in three age groups (4-6 years, 7-9 years and 13-14 years) was measured for 1 week in late summer (February-March) in Durban, South Africa, using UVR-sensitive polysulfone film badges (PSFB) attached to the lapel region of the body. The mean and median values for all ages over the study period were 2.0 and 1.2 standard erythemal dose (SED) units, respectively, where 1 SED = 100 J x m(-2). Individual PSFB doses were analyzed as a function of age, gender and behavior. No significant statistical differences were found between different age groups; however, there was a statistical difference between males and females, with males generally receiving higher PSFB doses. Subjects completed UVR exposure journals documenting their time outdoors, shade versus sun conditions, nature of their activities, clothing worn and their use of sunscreen for each day of the study. Activity patterns were noted as the most important factor influencing individual UVR dose. Ambient erythemal UVR was measured by a Yankee Environmental Systems UVB pyranometer, and a relationship between ambient UVR and individual UVR dose was derived. On average, subjects received a dose of 4.6% of the total daily erythemal UVR. Based on this factor, the potential dose of an individual over a full annual cycle was estimated. Accordingly, there were 139 days during the year when an individual with skin type I (light skin) would be likely to experience minimal erythema and 97 and 32 days for individuals with skin types II and III, respectively.     

The development of a National Accreditation System in South and Southern Africa

 In South African industry there is a strong appreciation of Quality Assurance. More than 1400 companies have been certified as complying with ISO 9000, and this, of course, has resulted in a strong demand for accredited calibration and test facilities. Work on the development of a national calibration service started in 1976, and the South African National Calibration Service (SANCS) was inaugurated in 1980 with 13 calibration laboratories. The early maturity of the SANCS can be judged by the fact that by 1984 it had the technical capability to establish a mutual recognition agreement with a European country. It now has a total of some 191 accredited laboratories, 139 calibration laboratories and 52 testing laboratories. In 1993, the SANCS signed mutual recognition agreements with the CNLA (Taiwan) and the European Co-operation for the Accreditation of Laboratories (EAL). In 1994 it entered the field of testing laboratory accreditation and is already experiencing a strong influence therefrom, and in 1997 it changed its name to National Laboratory Accreditation Service (NLA). In May 1995, the NLA was appointed by the Department of Trade and Industry to establish a South African National Accreditation System (SANAS). Progress with this work up to the present time has been substantial.     

Composition and biological potential of essential oil from Thelechitonia trilobata growing in South Africa

Thelechitonia trilobata is regarded as a troublesome weed that grows to form a dense blanket over the soil preventing the growth of other crops in farmland. Although the plant is regarded as a notorious, invasive plant, its chemical composition and biological potential have not been reported. The essential oil was isolated from the fresh leaves of T. trilobata using hydrodistillation. alpha-Pinene (21.6%), alpha-phellendrene (21.0%), limonene (12.8%) and germacrene D (7.5%) were the major constituents of the oil. The essential oil was screened against agricultural pests. The anti-tick properties were tested on Ripicephalus e. ervertsi found on sheep, while repellency, fumigation, and contact toxicity tests were carried out with maize weevils. Except for the contact toxicity test, all other bioassays gave positive results.     

The Influence of Non-Engineered Municipal Landfills on Groundwater Chemistry and Quality in Bloemfontein,South Africa

This study assessed the groundwater quality around two municipal solid waste landfill sites, in the city of Bloemfontein, Free State Province, South Africa. The two landfill sites are located in two contrasting geological terrains, with both lacking some basic facilities found in a well-designed landfill. A total of eight groundwater samples were collected from pollution monitoring boreholes near the two landfill sites, with five samples representing the northern landfill site and three samples representing the southern landfill site. The samples were collected in the autumn and winter seasons to assess any possible seasonal variations. They were analysed for physicochemical (pH, electrical conductivity (EC), total dissolve solids (TDS), chemical oxygen demand (COD) and total organic carbon (TOC)) and microbiological parameters (Escherichia coli, total coliform). The results of the analysis showed that the waters from both landfills were generally dominated by Ca, Mg, SO4, and HCO3 ions. Some of the major anions and cations in the water samples were above the South African National Standard (SANS241:2015) and World Health Organisation (WHO) permissible limits for drinking water. Majority of the boreholes had total dissolved solids and electrical conductivity values exceeding the SANS 241:2015 and WHO permissible limits. Piper trilinear plots for the two landfill sites showed that Ca(Mg)HCO3 water type predominates, but Ca(Mg)SO4 and Ca(Mg)Cl were also found. These water types were further confirmed with expanded Durov diagrams, indicating that that the boreholes represented a water type that is seldom found which is undergoing ion exchange, typical of sulphate contamination. From the SAR diagrams, boreholes in the northern landfill site had a high salinity hazard with only one borehole in the southern landfill site having a high salinity hazard. The geology was found to play a significant role in the distribution of contaminants into the groundwater systems in the study area. The study concluded that the northern landfill site had a poorer water quality in comparison to the southern landfill site based on the analysed physicochemical parameters. However, the southern landfill site showed significant microbial contamination, due to the elevated amount of E. coli and total coliform concentrations. The high permeability of the weathered dolerites in the northern landfill site might have enabled the percolation of contaminants into the groundwater resulting in the poorer water quality.     

Active biomonitoring of atmospheric pollution in the Western Cape (South Africa) using INAA and ICP-MS

Journal of Radioanalytical and Nuclear Chemistry - For the first time, active biomonitoring was used to assess elemental content of atmospheric pollution in selected areas of the Western Cape...     

A Comparison of Solar Ultraviolet Radiation Exposure in Urban Canyons in Venice,Italy and Johannesburg,South Africa

Urban environments can have high-risk spaces that can provide excess personal sun exposure, such as urban or street canyons, and the spaces between buildings, among others. In these urban spaces, sun exposure can be high or low depending on several factors. Polysulphone film (PSF) was used to assess possible daily solar ultraviolet radiation (UVR) exposure in urban canyons in Venice, Italy and, for the first time in Africa, in Johannesburg, South Africa. The photodegradation of PSF upon solar exposure was monitored at a wavelength of 330 nm by ultraviolet-visible spectrophotometry, and the resultant change was converted to standard erythemal dose (SED) units (1 SED = 100 J m⁻²). Mean daily ambient solar UVR exposure measured for Venice and Johannesburg ranged between 20–28 SED and 33–43 SED, respectively. Canyon-located PSF exposures were lower in Venice (1–9 SED) than those in Johannesburg (9–39 SED), depending mainly on the sky view factor and orientation to the sun. There was large variation in solar UVR exposure levels in different urban canyons. These preliminary results should be bolstered with additional studies for a better understanding of excess personal exposure risk in urban areas, especially in Africa.     

Quantitative Speciation of Arsenic in Water and Sediment Samples from the Mokolo River in Limpopo Province,South Africa

The Mokolo River is disposed to environmental contaminants such as arsenic (As) due to its proximity to several anthropogenic activities. Speciation of As in water and sediment samples from Mokolo River is crucial to evaluate the level and distribution of As in the river and underlying sediment since toxicity depends on its chemical forms. In this study, As species in water and sediment were determined by developing a new method for sediment extraction. Effective microwave-assisted extraction of As species in sediment samples was achieved using 0.3?M (NH₄)₂HPO₄ and 50?mM EDTA, which showed no species interconversion during extraction. The chromatographic separation and detection of As(III), dimethylarsinic acid (DMA), monomethylarsonic acid, and As(V) in water and sediment samples were achieved by coupling to high-performance liquid chromatography to inductively coupled plasma mass spectrometry. Baseline separation of four As species was achieved in 12?min using gradient elution with 10 and 60?mM NH₄NO₃ at pH 8.7 as the mobile phase. The analytical figures of merit and validation of analytical procedures were assessed and adequate performance and percentage recoveries ranging from 81.1 to 102% for water samples and 73.0–92.0% for sediments were achieved. The As species concentration in water and sediment samples was found to be in the range of 0.304–4.99?µg?L^?1 and 74.0–92.0?ng?g^?1, respectively. DMA was not detected in both water and sediment samples.     

Forensic performance of Investigator DIPplex indels genotyping kit in native,immigrant, and admixed populations in South Africa

The utilization of binary markers in human individual identification is gaining ground in forensic genetics. We analyzed the polymorphisms from the first commercial indel kit Investigator DIPplex (Qiagen) in 512 individuals from Afrikaner, Indian, admixed Cape Colored, and the native Bantu Xhosa and Zulu origin in South Africa and evaluated forensic and population genetics parameters for their forensic application in South Africa. The levels of genetic diversity in population and forensic parameters in South Africa are similar to other published data, with lower diversity values for the native Bantu. Departures from Hardy–Weinberg expectations were observed in HLD97 in Indians, Admixed and Bantus, along with 6.83% null homozygotes in the Bantu populations. Sequencing of the flanking regions showed a previously reported transition G>A in rs17245568. Strong population structure was detected with Fst, AMOVA, and the Bayesian unsupervised clustering method in STRUCTURE. Therefore we evaluated the efficiency of individual assignments to population groups using the ancestral membership proportions from STRUCTURE and the Bayesian classification algorithm in Snipper App Suite. Both methods showed low cross‐assignment error (0–4%) between Bantus and either Afrikaners or Indians. The differentiation between populations seems to be driven by four loci under positive selection pressure. Based on these results, we draw recommendations for the application of this kit in SA.     

Chemical Profiling,Toxicity and Anti-Inflammatory Activities of Essential Oils from Three Grapefruit Cultivars from KwaZulu-Natal in South Africa

The medicinal potential and volatile composition of different parts of three cultivars of grapefruit (Citrus paradisi) were evaluated for their toxicity and anti-inflammatory activities. Fresh leaf and fruit peel were separately isolated by hydrodistillation for 4 h. The essential oils were subjected to GC/GC-MS analysis for chemical profile. Toxicity of the essential oils in mice were evaluated using Lorke’s method, while an anti-inflammatory assay was performed in a rat model using egg albumin-induced oedema. The oils obtained were light yellow in colour, and odour varied from strong citrus smell to mild. Percentage yield of fresh peel oil (0.34–0.57%) was greater than the fresh leaf oil yield (0.21–0.34%). D-limonene (86.70–89.90%) was the major compound identified in the leaf oil, while β-phellandrene (90.00–91.01%) dominated the peel oil. At a dosage level of 5000 mg/kg, none of the oils showed mortality in mice. An anti-inflammatory bioassay revealed that all the oils caused a significant (p < 0.05–0.01) reduction in oedema size when compared to the negative control group throughout the 5 h post induction assessment period. The study reveals that the oils are non-toxic and demonstrate significant anti-inflammatory activity. Our findings suggest that the leaf and peel oils obtained from waste parts of grapefruit plants can be useful as flavouring agents, as well as anti-inflammatory agents.     

A Raman microprobe study of melt inclusions in kimberlites from Siberia, Canada, SW Greenland and South Africa

The geometries, energies and vibrational frequencies of various polyborates in both gaseous and aqueous phase were calculated at the B3LYP/aug-cc-pVDZ level. The calculated total symmetrical stretching Raman shifts of B(OH)(3), B(OH)(4)(-), B(2)O(OH)(4), B(2)O(OH)(5)(-), B(2)O(OH)(6)(2-), B(3)O(3)(OH)(3), B(3)O(3)(OH)(4)(-), B(3)O(3)(OH)(5)(2-), B(3)O(3)(OH)(6)(3-), B(4)O(5)(OH)(4)(2-) and B(5)O(6)(OH)(4)(-) were assigned to 877.40, 735.33, 785.22, 792.90, 696.79, 587.72, 599.06, 740.16, 705.01, 551.67 and 521.04cm(-1), respectively. The results can be used as the characteristic frequency for polyborates in aqueous phase at room temperature. At least six types of polyborates B(OH)(3), B(OH)(4)(-), B(3)O(3)(OH)(4)(-), B(3)O(3)(OH)(5)(2-), B(4)O(5)(OH)(4)(2-) and B(5)O(6)(OH)(4)(-), occur in aqueous solutions at ambient temperature. The chemical species distribution and the relevant interaction mechanisms among polyborates in the solutions were also suggested.     

Novel method for determining DDT in vapour and particulate phases within contaminated indoor air in a malaria area of South Africa

The organochlorine insecticide DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is still used for malaria vector control in certain areas of South Africa. The strict Stockholm Convention on Persistent Organic Pollutants (POPs) allows spraying on the inside of traditional dwellings with DDT. In rural villages contaminated dust presents an additional pathway for exposure to DDT. We present a new method for the determination of DDT in indoor air where separate vapour and particulate samples are collected in a single step with a denuder configuration of a multi-channel open tubular silicone rubber (polydimethylsiloxane (PDMS)) trap combined with a micro quartz fibre filter. The multi-channel PDMS trap section of the denuder concentrates vapour phase insecticide whereas particle associated insecticide is transferred downstream where it is collected on a micro-fibre filter followed by a second multi-channel PDMS trap to capture the blow-off from the filter. The multi-channel PDMS trap and filter combination are designed to fit a commercial thermal desorber for direct introduction of samples into a GC–MS. The technique is solvent-free. Analyte extraction and sample clean-up is not required. Two fractions, vapour phase and particulate phase p,p′-DDT, o,p′-DDT; p,p′-DDD, o,p′-DDD; p,p′-DDE and o,p′-DDE in 4 L contaminated indoor air, were each quantitatively analysed by GC–MS using isotopically labelled ring substituted ¹³C₁₂ – p,p′-DDT as an internal standard. Limits of detection were 0.07–0.35 ng m⁻³ for p,p′-DDT, o,p′-DDT, p,p′-DDD, o,p′-DDD, p,p′-DDE and o,p′-DDE. Ratios of airborne p,p′-DDD/p,p′-DDT and of o,p′-DDT/p,p′-DDT are unusual and do not match the ideal certified ingredient composition required of commercial DDT. Results suggest that the DDT products used for indoor residual spraying (IRS) prior to, and during 2007, may have been compromised with regards to insecticidal efficacy, demonstrating the power of this new environmental forensics tool.     

Verification of nitrous oxide primary standard gas mixtures by gas chromatography and cavity ring-down spectroscopy for ambient measurements in South Africa

Accreditation and Quality Assurance - Nitrous oxide (N2O) is an important greenhouse gas and is the third-largest contributor to global warming with a global warming potential (GWP) higher than...     

Effect of Soil Type: Qualitative and Quantitative Analysis of Phytochemicals in Some Browse Species Leaves Found in Savannah Biome of South Africa

In semi-arid regions, browse plant species are used as feed and for medicinal purposes for both animals and humans. The limitation of the utilization of these species to medicinal purposes or as feed for livestock is a lack of knowledge on the concentration level of phytochemicals and other bioactive compounds found in these plants. The study sought to assay the qualitative and quantitative bioactive constituents of some browse species found in the savannah biome of South Africa, viz. Adansonia digitate, Androstachys johnsonii, Balanites maughamii, Berchemia discolor, Berchemia zeyheri, Bridelia mollis hutch, Carissa edulis, Catha edulis, Colophospermum mopane, Combretum Imberbe, Combretum molle, Combretum collinum, Dalbergia melanoxylon, Dichrostachys cinerea, Diospros lycioides, Diospyros mespiliformis, Euclea divinorum, Flueggea virosa, Grewia flava, Grewia flavescens, Grewia monticola, Grewia occidentalis, Melia azedarach, Peltophorum africanum, Prosopis velutina, Pseudolachnostylis maprouneifolia, Pterocarpus rotundifolius, Schinus molle, Schotia brachypetala, Sclerocarya birrea, Searsia lancea, Searsia leptodictya, Searsia pyroides, Senegalia caffra, Senegalia galpinii, Senegalia mellifera, Senegalia nigrescens, Senegalia polyacantha, Strychnos madagascariensis, Terminalia sericea, Trichilia emetic, Vachellia erioloba, Vachellia hebeclada, Vachellia karroo, Vachellia nilotica, Vachellia nilotica subsp. Kraussiana, Vachellia rechmanniana, Vachellia robusta, Vachellia tortilis, Vachellia tortilis subsp. raddiana, Vangueria infausta, and Ziziphus mucronata. These browse species’ leaf samples were harvested from two provinces (Limpopo and North-West) of South Africa. The Limpopo province soil type was Glenrosa, Mispah, and Lithosols (GM-L), and the soil types in the North-West Province were Aeolian Kalahari Sand, Clovelly, and Hutton (AKS-CH). The harvested browse samples were air dried at room temperature for about seven days and ground for analysis. The methanol and distilled water extracts of the browse species leaves showed the presence of common phytoconstituents, including saponins, flavonoids, tannins, phenols, cardio glycosides, terpenoids, and phlobatannins, as major active compounds in browse species leaves. In the quantitative analysis, phytochemical compounds, such as soluble phenols, insoluble tannins, and condensed tannins, were quantified for common species found in both sites. Two-way ANOVA and multivariate analysis were used to test soil type and species effect on soluble phenols, insoluble tannins, and condensed tannins of woody species. Dichrostachys cinerea (0.1011% DM) in GM-L soil type and Z. mucronata (0.1009% DM) in AKS-CH soil type showed the highest (p < 0.05) concentration of soluble phenols. In AKS-CH soil type, D. cinerea (0.0453% DM) had the highest insoluble tannins concentration, while V. hebeclada had the lowest (0.0064% DM) insoluble tannins content. Vacchelia hebeclada had lower (p < 0.05) condensed tannins concentration levels than all other browse plants in both soil types. Under multivariate analysis tests, there was a significant effect (p < 0.001) of soil type, species, and soil type x species interaction on soluble phenols, insoluble tannins, and condensed tannins of woody species. In this study, most of the woody species found in GM-L soil type showed a lower amount of tannins than those harvested in AKS-CH soil type. There is a need to identify the amount of unquantified phytochemicals contained in these browse species and valorize the high-bioactive-compound browse species to enhance and maximize browsing of these browse species for animal production.     

气球中N-亚硝胺及其前体物迁移量的测定与NDMA的儿童致癌暴露风险分析

用Sep-Pak AC2串联Dry cartridges固相萃取小柱对气球中的7种挥发性N-亚硝胺进行分离净化,并用气相色谱-串联质谱法对其进行定性与定量分析。方法对气球中N-亚硝胺及其前体物的检出限分别为1.25μg/kg和5.00μg/kg。对空白样品进行添加量为2.5μg/kg的加标回收实验,回收率为85%～103%,RSDs(n=3)≤4.6%。分析的气球样品中,N-亚硝基二甲胺(NDMA)及其前体物的检出频率最高;其次是N-亚硝基二乙胺(NDEA)及其前体物;N-亚硝基吗啉(NMOR)、N-亚硝基二丙胺(NDPA)和N-亚硝基哌啶(NPIP)及其前体物均未检出;7种N-亚硝胺及其前体物的总迁移量分别为0.036～0.964 mg/kg和0.259～8.436 mg/kg。6个月～4岁儿童通过口直接接触单个气球样品造成的NDMA的暴露量集中在0.010～0.030mg/kg体重,具有潜在的致癌暴露风险。