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We investigated presence and levels of DDT in 163 breast milk samples from four South African villages where, in three of them, malaria is controlled with DDT-sprayed indoors. Mean ΣDDT levels in breast milk were 18, 11, and 9.5 mg/kg mf (milk fat) from the three DDT-sprayed villages, respectively, including the highest ΣDDT level ever reported for breast milk from South Africa (140 mg/kg mf). Understanding the causes for these differences would be informative for exposure reduction intervention. The Provisional Tolerable Daily Intake (PTDI) for DDT by infants, and the Maximum Residue Limit (MRL) were significantly exceeded. DDT had no effect on duration of lactation. There were indications (not significant) from DDT-sprayed villages that first-born female infants drink milk with more ΣDDT than first-born male infants, and vice versa for multipara male and female infants, suggesting gender involvement on levels of DDT in breast milk - requiring further investigation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The partitioning of α- and γ-hexachlorocyclohexane between air and the moss Hylocomium splendens and the lichen Cladina stellaris were studied under laboratory conditions. After cultivation of the sample material to obtain a common starting point free from outside influence, the material was divided into four different treatment categories with different hydration/desiccation regimes. The concentrations of the analytes were 3-5 times higher in the hydrated moss or lichen than in the desiccated material. The results are in contrast to how these compounds are taken up by pine needles in which there is a continuous accumulation, more rapid during periods with high temperatures and dry weather. In general, the different adaptations to water economy is a more important explanatory factor for the concentration of airborne hydrophobic pollutants in mosses, lichens, and vascular plants than their designation as "plants" in a broad sense. It is, therefore, not advisible to mix data from different organism groups for monitoring or modeling purposes.

We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the world's third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560 km east of the island of Mauritius. ΣPCBs had the highest levels (2.2 and 2.6n g/g wm, wet mass; 20 and 19 ng/g lm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then ΣDDT (1.9 and 3.1 ng/g wm; 17 and 23 ng/g lm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0 ng/gl m). ΣChlordanes (0.094 and 0.15 ng/g wm; 0.48 and 0.73 ng/g lm) and Σtoxaphenes (0.26 and 0.61 ng/g wm; 2.4 and 5.9 ng/g lm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07 ng/g wm; 0.7 and 0.7 ng/g lm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Σchlordanes and Σtoxaphenes, as well as CB105, -108 and -157. p,p'-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Inhabitants of dwellings treated with DDT for indoor residual spraying show high DDT levels in blood and breast milk. This is of concern since mothers transfer lipid-soluble contaminants such as DDT via breastfeeding to their children. Focusing on DDT use in South Africa, we employ a pharmacokinetic model to estimate DDT levels in human lipid tissue over the lifetime of an individual to determine the amount of DDT transferred to children during breastfeeding, and to identify the dominant DDT uptake routes. In particular, the effects of breastfeeding duration, parity, and mother's age on DDT concentrations of mother and infant are investigated. Model results show that primiparous mothers have greater DDT concentrations than multiparous mothers, which causes higher DDT exposure of first-born children. DDT in the body mainly originates from diet. Generally, our modeled DDT levels reproduce levels found in South African biomonitoring data within a factor of 3., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This study deals with disorders of sexual development in humans, wildlife and animals in an urban nature reserve (RNR) and a currently DDT-sprayed malarial area. High levels of oestrogenic chemical residues in water, sediment and tissue; skewed sex ratios; reduced biodiversity; gonadal malformations in sharptooth catfish and freshwater snails; intersex in catfish; and impaired spermatogenesis in catfish and striped mouse are of serious concern in the RNR. Persistent eggshell thinning in African darter eggs, intersex in male Mozambican tilapia, follicular atresia in females and impaired spermatogenesis in males following laboratory exposure of parent fish to environmentally relevant DDT and DDE concentrations, and abnormalities in freshwater snails were found in the DDT-sprayed area. Human studies related to DDT exposure indicated impaired semen quality, a weak association with sperm chromatin defects and higher risks for external urogenital birth defects in those who were born to mothers whose houses were sprayed and those who were homemakers (stay at home mother) instead of being employed. These findings indicate that diseases of sexual development occurred in both human and wildlife populations exposed to environmental endocrine disruptor chemicals in South Africa. The chemical mixtures, possibly related to disorders of sexual differentiation (DSD), were very different between the two. However, DSD occurred concurrently in the malarial area, possibly indicating that humans and wildlife shared exposures. Moreover, it emphasizes the importance of suspecting disease in the other when disease is found in either human or wildlife populations., (© 2012 Blackwell Verlag GmbH.)

Malaria is still responsible for 10% of the total disease burden in Africa. This study was an empirical investigation addressing the extent to which, and the ways in which, sociocultural, family-based, demographic and economic circumstances in a poor rural African environment influence levels of active malaria infection risk awareness. Face-to-face interviews were conducted and the questions included both open-ended questions allowing for unprompted replies and closed fixed-answer alternative (prompted) items. The adult female responsible for the day-to-day care of the children in 156 homesteads (60 in each of two malaria villages and 36 in a reference village) was interviewed. The families received financial assistance but little physical support from the fathers. Unemployment, poverty, crime and clean water were perceived as the main, unprompted threats, and everyday awareness appeared to exclude the potentially serious disease threats of malaria. Only when malaria was prompted did the concerns rise to 52% and 38% in the sprayed villages. The apparent discrepancy between actual daily and potential future threats significantly increases the difficulty of mobilising communities for preventive action regarding potential threats. The lack of community involvement in an existing community-passive malaria control system may become a problem when promoting new/additional measures to reduce exposure to indoor residual spraying chemicals., (Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

Background: The debate regarding dichlorodiphenyltrichloroethane (DDT) in malaria prevention and human health is polarized and can be classified into three positions: anti-DDT, centrist-DDT, pro-DDT., Objective: We attempted to arrive at a synthesis by matching a series of questions on the use of DDT for indoor residual spraying (IRS) with literature and insights, and to identify options and opportunities., Discussion: Overall, community health is significantly improved through all available malaria control measures, which include IRS with DDT. Is DDT "good"? Yes, because it has saved many lives. Is DDT safe as used in IRS? Recent publications have increasingly raised concerns about the health implications of DDT. Therefore, an unqualified statement that DDT used in IRS is safe is untenable. Are inhabitants and applicators exposed? Yes, and to high levels. Should DDT be used? The fact that DDT is "good" because it saves lives, and "not safe" because it has health and environmental consequences, raises ethical issues. The evidence of adverse human health effects due to DDT is mounting. However, under certain circumstances, malaria control using DDT cannot yet be halted. Therefore, the continued use of DDT poses a paradox recognized by a centrist-DDT position. At the very least, it is now time to invoke precaution. Precautionary actions could include use and exposure reduction., Conclusions: There are situations where DDT will provide the best achievable health benefit, but maintaining that DDT is safe ignores the cumulative indications of many studies. In such situations, addressing the paradox from a centrist-DDT position and invoking precaution will help design choices for healthier lives.

Background, Aim, and Scope: The blue swallow (Hirundo atrocaerulea) is one of the most threatened bird species in southern Africa. Among terrestrial birds, its plumage is known to be the most water repellent, an adaptation to foraging on the wing in dense fog. Despite this unique adaptation, the nesting success of the blue swallow at the Blue Swallow Natural Heritage Site (BSNHS) is lower during years with high incidence of fog. As the phenomenon is not observed at other nesting sites, we hypothesized that this is due to changes in the air chemistry at the BSNHS. In the immediate proximity of the BSNHS, plantations of exotic trees (e.g., pines and eucalypts), rich in volatile organic compounds (VOCs), are dominant features. In addition, air pollution from the Johannesburg area is transported with the surface winds and mix with VOCs released from exotic trees. Together with the high humidity and high elevation, these conditions may result in the formation of sulphonates. Sulphonates are strong detergents, and the presence of these in the fog could lead to decreased water repellence of the plumage. This study was performed in order to determine the occurrence and distribution of sulphonates in the BSNHS and to compare these with sulphonates formed in other locations in South Africa. Because the blue swallow is endangered, pine needles were used as proxy to detect formation of sulphonates., Methods: We sampled pine needles with different exposure to air pollutants, in climates with different humidity, and at different elevation and analyzed these for sulphonates using mass spectrometry., Results: Pine needles from high elevations and the BSNHS, with high humidity, and exposure to air pollution contained significantly higher concentrations of sulphonates than pine needles from low elevations or from high elevations with a dryer climate or a different combination of air pollutants., Conclusions: These findings lead to two conclusions. First, the occurrence and distribution of sulphonates may be explained by chemical reactions between sulphur dioxide and organic compounds in the humid air induced by ultraviolet radiation. Second, elevated concentrations of sulphonates in the fog could affect the water repellence of the blue swallow plumage, possibly decreasing their capacity to forage in the fog. We cannot prove conclusively that this is the reason why the number of blue swallows at the BSNHS has decreased dramatically, but for endangered species, we may have to rely on proxies to draw conclusions about outside threats. All such information should be valuable in devising protection plans for species under threat., Recommendations and Perspectives: The use of proxies to elucidate threats to endangered species should be evaluated in a broad scale. The mist-belt habitat in general is threatened by many human activities. These findings indicate that air pollution and the proximity of volatile organic compound (VOC) sources close to mist-belt habitat refuges may be an unrecognised conservation threat to the animals inhabiting them.

The results presented describe and compare the fatty acid composition and melting properties of captive, healthy wild, and pansteatitis-affected wild crocodiles (Crocodylus niloticus). Differences in fatty acid composition between intramuscular and adipose fat is noted in captive crocodiles, and the latter differs from wild crocodiles as a result of different diets. Adipose fat of healthy wild crocodiles differs minimally from diseased ones, respectively with 37.3+/-2.6% vs. 43.2+/-2.3% monounsaturated fatty acids, and 43.2+/-2.9% in dead crocodiles, while polyunsaturated fatty acids decrease from 27.3+/-1.9% to as low as 21.9+/-3.6% respectively. Of the unsaturated fatty acids 18:2n-6 decreased from 6.5+/-2.6% in unaffected crocodiles to 3.5+/-0.6% in highly affected and 3.2+/-0.4% in dead crocodiles, and 22:5n-3 from 2.8+/-0.6% to 1.8+/-0.3% and 2.2+/-0.3% respectively. The melting properties as determined by differential scanning calorimetry show that extracted adipose fat is a small degree softer in pansteatitis-affected tissue, specifically in the temperature range 7-36 degrees C, and does not contribute to the hard texture noted for adipose fat tissue of pansteatitis-affected animals. A high moisture content of 51.0+/-19.7% of the fat tissue of pansteatitis-affected animals vs.17.1+/-8.0% of healthy ones, suggests that physiological changes due to interstitial inflammation may contribute to the hard texture.

Background: In many parts of the world, deliberate indoor residual spraying (IRS) of dwellings with insecticides to control malaria transmission remains the only viable option, thereby unintentionally but inevitably also causing exposure to inhabitants. Because mothers are exposed to insecticides via various routes, accumulated residues are transferred to infants via breast milk, in some cases exceeding recommended intake levels. Except for dichlorodiphenyltrichloroethane (DDT), safety of residues of other insecticides in breast milk has not been considered during World Health Organization Pesticide Evaluation Scheme (WHOPES) evaluations. However, very little is known of the health risks posed by these chemicals to infants who, in developing countries, breast-feed for up to 2 years., Objective: We evaluated the need for WHOPES to include breast milk as a potentially significant route of exposure and risk to infants when evaluating the risks during evaluation of IRS insecticides., Discussion: We present evidence showing that neurologic and endocrine effects are associated with pyrethroids and DDT at levels equal or below known levels in breast milk., Conclusions: Because millions of people in malaria control areas experience conditions of multiple sources and routes of exposure to any number of insecticides, even though lives are saved through malaria prevention, identification of potential infant health risks associated with insecticide residues in breast milk must be incorporated in WHOPES evaluations and in the development of appropriate risk assessment tools.

Currently very little data exists on the presence of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in the South African environment. To address this data gap a preliminary study of a highly industrialised area of South Africa, the Vaal Triangle, was done. Soil and sediment samples from the Vaal Triangle, as well as other areas in central South Africa, were analysed with high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) for the presence of PAHs, polychlorinated biphenyls (PCBs), dioxin-like chemicals and organochlorine pesticides (OCPs). Results showed that these chemicals are present in the South African environment with concentrations ranging between 39,000 ng g(-1) for SigmaPAHs and 0.01 ng g(-1) for dicofol. Principal component analysis (PCA) indicated different pollution sources in industrial and agricultural areas.

Objectives: Dichlorodiphenyltrichloroethane (DDT) was used worldwide until the 1970s, when concerns about its toxic effects, its environmental persistence, and its concentration in the food supply led to use restrictions and prohibitions. In 2001, more than 100 countries signed the Stockholm Convention on Persistent Organic Pollutants (POPs), committing to eliminate the use of 12 POPs of greatest concern. However, DDT use was allowed for disease vector control. In 2006, the World Health Organization and the U.S. Agency for International Development endorsed indoor DDT spraying to control malaria. To better inform current policy, we reviewed epidemiologic studies published from 2003 to 2008 that investigated the human health consequences of DDT and/or DDE (dichlorodiphenyldichloroethylene) exposure., Data Sources and Extraction: We conducted a PubMed search in October 2008 and retrieved 494 studies., Data Synthesis: Use restrictions have been successful in lowering human exposure to DDT, but blood concentrations of DDT and DDE are high in countries where DDT is currently being used or was more recently restricted. The recent literature shows a growing body of evidence that exposure to DDT and its breakdown product DDE may be associated with adverse health outcomes such as breast cancer, diabetes, decreased semen quality, spontaneous abortion, and impaired neurodevelopment in children., Conclusions: Although we provide evidence to suggest that DDT and DDE may pose a risk to human health, we also highlight the lack of knowledge about human exposure and health effects in communities where DDT is currently being sprayed for malaria control. We recommend research to address this gap and to develop safe and effective alternatives to DDT.

Persistent organic pollutants (POPs) are a global concern due to their ubiquitous presence and toxicity. Currently, there is a lack of information regarding POPs from South Africa. Here we report and interpret concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and co-planar-biphenyls (PCBs) in soils and sediments collected from central South Africa. High resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) and the H4IIE-luc bio-assay were used to identify and quantify individual PCDD/F congeners and to report the total concentration of 2,3,7,8-tetrachloro dibenzo-p-dioxin equivalents (TCDD-EQ), respectively. TCDD-EQs determined by use of the bio-assay, and concentrations of WHO(2005)-TEQ (toxic equivalents) determined by chemical analysis, were similar. The limit of detection (LOD) for the bio-assay was 0.82 and 2.8 ng TCDD-EQ kg(-1), dw for sediment and soil, respectively. EQ20 concentrations determined by use of the bio-assay ranged from

The presence of pollutants in human breast milk is of major concern, especially in malaria control areas where 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) is currently used as indoor residual spray (IRS). The levels of DDT and pyrethroids (PYR) were determined in breast milk, bovine milk, and drinking water from northern KwaZulu-Natal, South Africa. Both reference and exposed mothers used the same market food, but the DDT levels in the exposed mothers (mean SigmaDDT 10 microg/g milk fat [mf]) were much higher than for the reference mothers (mean SigmaDDT 1.3 microg/g milk fat). This difference in residue levels indicates uptake from IRS-applied DDT, most likely via air and skin contact, and excludes food as the main source of pollutants. DDT levels in bovine milk (mean SigmaDDT 0.15 microg/g mf) from the exposed area were less than levels in breast milk from the reference area, and lower than the 20 microg/L maximum residue limit (MRL) set by the Food and Agriculture Organization (FAO). Mean SigmaDDT in water was 0.0065 microg/L, much lower then the WHO limit of the sum of all metabolites in drinking water of 1 microg/L, and therefore highly unlikely to have contributed to any extent toward levels in breast milk. Permethrin in breast milk (mean 1.1-1.6 microg/g milk fat) was probably derived from home garden and indoor use, while the other PYR (cypermethrin and cyfluthrin) at lower concentrations were probably derived from food and agricultural exposure. It is postulated that a better understanding of the indoor dynamics of DDT and other insecticides, through a concept of Total Homestead Environment Approach (THEA), is crucial for investigating options of reducing human exposure and uptake under malaria control conditions.

During the last 15 years, no research has been published on the levels of pesticides in bird eggs from South Africa, despite the high levels found previously. We analysed eggs from African darter, cattle egret, reed cormorant, African sacred ibis, as well as single eggs from some other species, and found HCB, DDTs, HCHs, chlordanes and PCBs at detectable levels. The presence of mirex in all species was unexpected, since this compound was never registered in South Africa. It also seemed as if terrestrial feeding birds had higher DDE:PCB ratios when compared with aquatic feeding birds. Except for chlordane, the African darter eggs had the highest levels of all other compounds (mean 370 and 300 ng g(-1) ww Sigma pesticides and Sigma PCBs, respectively). Multivariate analysis clearly distinguished the aquatic and terrestrially feeding birds on pollution profile. The African darter (aquatic feeding) and the cattle egret (terrestrial feeding) would be good indicator candidates. Eggshell thinning was detected in the African darter, and was associated with most of the compounds, including DDE and PCBs. We raise a concern that generally longer living birds in warmer climates, laying fewer eggs per clutch, might be at increased risk when compared with trophically similar birds exposed to equivalent levels of pollution in colder climates. Given the scarcity of water and the high biodiversity in Southern Africa, climate change will exert strong pressure, and any additional anthropogenic contamination at levels that can cause subtle behavioural, developmental and reproductive changes, can have serious effects.

Gas chromatography was used to establish the presence of quantifiable residues of 14 persistent chlorinated hydrocarbon pollutants in whole blood, clotted blood, heart, kidney, liver and muscle samples obtained from individual African whitebacked (Pseudogyps africanus), Cape griffon (Gyps coprotheres) and Lappetfaced (Torgos tracheliotos) vultures from different localities in South Africa. The levels of pesticides measured in whole blood samples of live specimens were compared between nestlings from two natural breeding colonies, adults from a wildlife area and birds held in captivity. Statistically significant (P<0.05) differences between populations were detected in geometric means calculated for gamma-BHC (lindane), alpha(cis)-chlordane and alpha-endosulfan. Five of the organochlorine contaminants displayed significant variations between concentrations detected in the clotted blood, organs and muscles excised from vulture carcasses. This includes residues of gamma-BHC, alpha-chlordane, dieldrin, beta-endosulfan and heptachlor epoxide. Values of the respective biocides measured in vulture samples were generally low in comparison to results documented for a number of avian species. Although no threat is posed by any of the organochloride pesticides, continual monitoring of especially breeding colonies is recommended. Furthermore, the suitability of African whitebacked vulture nestlings as basic bioindicators is highly advocated.

Blood samples were obtained on four occasions over a 12-month period from individuals living in KwaZulu, South Africa, who had been exposed to DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) as a consequence of its use in their homes to control transmission of malaria. The longitudinal changes in serum DDT and its major metabolities, DDE and DDD, were determined. No additional risk was considered to have been presented by the increases that occurred following application of the pesticide. There were significant increases in DDT, DDE and sigma DDT (DDT + its metabolites) for the age group > or = 21 years, but for the age group 3-20 years a reduction in serum levels occurred over 12 months. Two concurrent processes probably govern the increase and decrease in serum levels, and the relative contributions of each interchange as the individual becomes older. The results suggest that children in KwaZulu experience conditions that differ from those of their parents, as well as from those that affect children in developed countries. In consequence, it is desirable that risk assessments of vector control chemicals consider all sectors of a population.

The transfer of p,p'-DDT (1,1,1-tricholoro-2,2-bis(4-chlorophenyl)ethane) and its metabolites to infants via breast-feeding was studied in an area of KwaZulu, South Africa, where DDT is used to interrupt malaria transmission. Samples of whole blood were collected from 23 infants, together with samples of breast milk from their respective mothers. The mean sigma DDT (total DDT) in the whole blood was 127.03 micrograms.l-1 and that in the breast milk, 15.06 mg.kg-1 (milk fat). The % DDT (% DDT of sigma DDT) was significantly higher in the infant blood than in the breast milk (P less than 0.05). A multiplicative regression analysis indicated that sigma DDT increased significantly (P less than 0.01) in infant whole blood with infant age. Multiple regression showed that 70.0% of the variation in sigma DDT was due to the variation in parity of the mother, age of the infant, and the sigma DDT in breast milk. These variables accounted also for 76.3% of the variation in p,p'-DDE but only for 38.2% of that in p,p'-DDT. Organochlorines were therefore largely transferred to the infant from the mother, with DDT in the environment playing a secondary role.

The levels of DDT and metabolites in serum of 23 applicators involved in malaria control operations in Natal were determined using gas chromatography with electron capture detection. The mean levels (microgram/l, ppb) were 61.7 DDT, 129.3 DDE, 11.0 DDD and 202.0 sigma DDT. Percentage DDT was 33.4%. These levels were higher than for an age matched sample of the general population in KwaZulu, who are protected by DDT against malaria. Percentage DDT correlated negatively with age (P less than 0.05) for the applicators, suggesting a change in pharmacodynamics with age. Mean serum albumin, alkaline phosphatase, aspartate transferase and gamma-glutamyltransferase (GGT) levels did not differ significantly from an age-matched control group, but the mean GGT value for the applicators was higher than the maximum of the laboratory normal range. Although not clinically significant, the alanine transferase was significantly higher in the applicators than in the control group. These higher levels suggest a possible risk to the health of the sprayers, but uncertainties remain.

Concentrations of DDT, DDE and DDD were determined in the breast milk of Kwa-Zulu mothers residing in two different areas--with and without annual intra-domiciliary applications of DDT for the interruption of malaria transmission (exposed and control groups, respectively). While no significant change in levels with time was found in the control group, both DDT and DDE in breast milk of the exposed group increased after DDT application and this continued for three more months, after which it did not decrease appreciably. Percentage DDT increased from 42.57% (sigma DDT = 12.21 mg/kg milk fat) before spraying to 50.87% (sigma DDT = 13.79 mg/kg milk fat) following DDT application. At 6 and 9 months after the application it was 45.85% (sigma DDT = 19.49 mg/kg milk fat) and 43.27% (sigma DDT = 18.34 mg/kg milk fat), respectively. These results suggest a risk to the health of the infants in the exposed group.