Factors affecting the transfer of organochlorine pesticide residues to breastmilk

Existing studies monitoring organochlorine pesticide residues in breastmilk were examined to identify whether common factors determine the extent of transfer of these residues. A structured review of the English language literature was conducted. Papers were reviewed and assessed using a structured protocol. A total of 77 papers were initially identified, 46 of which contained conclusions relating to the factors which may affect the transfer of residues into breastmilk. Owing to the diversity of findings, papers were screened further to include only those in which a minimum of background information relating to selection of mothers and to milk sampling procedures were reported. Only eight papers were deemed to contain adequate information. Age, parity/length of previous lactation, fat mobilisation and the time of sampling were identified as the most likely factors to be considered when assessing transfer of organochlorine pesticide residues into breastmilk. This review highlights the difficulties of assessing trends in breastmilk contaminants where comparable sampling procedures are not used.     

Mycosporine-like amino acids: possible UV protection in eggs of the sea hare Aplysia dactylomela

We investigated mycosporine amino acid (MAA) involvement as protective sunscreens in spawn of the sea hare Aplysia dactylomela to determine if adult diet and ultraviolet (UV) exposure affected the UV sensitivity of developing embryos. Adults were fed a red alga rich in MAAs (Acanthophora spicifera) or a green alga poor in MAAs (Ulva lactuca). Adults on each diet were exposed for 2 wk to ambient solar irradiance with two types of acrylic filters; one allowed exposure to wavelengths >275 nm (designated UV) and one to wavelengths only >410 nm (designated NOUV). Spawn from each adult group was likewise treated with UV or NOUV and monitored during development for differences in mortality and metabolic rate (measured as oxygen consumption: V˙ _O2). Also recorded were number of eggs or embryos per capsule, times to hatching, hatching success, size at hatching, and V˙ _O2 of adults. Spawn from adults eating red algae was almost twice as rich in MAAs as spawn from adults eating green algae, suggesting that MAA content is diet-related. Although overall quantities of MAAs in the spawn reflected MAA contents of the adult diet, specific MAAs were differentially sequestered in the spawn. Thus, porphyra-334, found in high concentration in Aplysia dactylomela's preferred red algal food, was present in only low concentration in the spawn. Conversely, mycosporine-glycine, in low concentration in red algal food, was the most abundant MAA in the spawn. UV treatment of adults had no effect on quantities of MAAs in the spawn. Adults exposed to UV had significantly higher V˙ _O2s and spawned twice as often. The UV-treated adults produced spawn with significantly higher V˙ _O2s and their embryos developed to hatching sooner. The only significant effect of UV exposure of the spawn was to reduce the percentage of veligers hatching from 71 to 50%. There was no significant effect on hatching time or size of the veligers at hatching, nor on number of eggs per capsule. Received: 13 May 1997 / Accepted: 27 June 1997     

Framing an independent,integrated and evidence-based evaluation of the state of Australia's biophysical and human environments

A new approach was developed for Australia's 2011 national State of the Environment (SoE) report to integrate the assessment of biophysical and human elements of the environment. A Common Assessment and Reporting Framework (CARF) guided design and implementation, responding to jurisdictional complexity, outstanding natural diversity and ecosystem values, high levels of cultural and heritage diversity, and a paucity of national-scale data. The CARF provided a transparent response to the need for an independent, robust and evidence-based national SoE report. We conclude that this framework will be effective for subsequent national SoE assessments and other integrated national-scale assessments in data-poor regions.     

Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity

Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input, and suitability of dredging are related to mud-sediment properties and provenance.     

VILLAGE DEMONSTRATION OF BIOGAS TECHNOLOGY: AN EGYPTIAN CASE STUDY

Within the context of biogas R & D and demonstration project undertaken by the Egyptian National Resarch Centre, village demonstrations are of paramount importance. In this paper, a case study of a pioneering village demonstration is presented. Based on a preliminary sociological survey, “Al Manawat” - a traditional Egyptian village was selected for the first demonstration. After a short orientation phase through which the biogas technology was introduced to a group of village representatives, a family was selected to conduct the demonstration experiment. Concomitant with the family energy requirements, availability of digester feed materials, site characteristics and other relevant factors, a family-size unit of a modified Indian type was designed and erected by the side of the farmer's house. The digester effective volume is 9 cu.m. and is connected to both a latrine and animal shed. The unit has been successfully operated since May 1981. The highlights of the construction stage as well as the unit performance characteristics are discussed. A preliminary techno-economic appraisal is also outlined. Finally, social impacts are assessed. Initial results indicate that under the Egyptian village conditions, and particularly with the heavily subsidized fuel prices, the high saving in manure transport attained through the introduction of the biogas unit, appears to be the main benefit from the farmer's point of view. Dans le cadre de la recherche et du développement du gaz de fermentation et d'un projet pilote entrepris par le Centre national de recherche égyptien, les démonstrations faites dans les villages occupent une place prépondérante. Dans cet article, l'auteur présente le cas-type d'une démonstration pilote faite dans un village. En se basant sur une enquêue sociologique préliminaire, “Al Manawat”, qui est un village égyptien traditionnel, a été choisi comme lieu de la première démonstration. Après une courte phase d'orientation au cours de laquelle le technologie du gaz de fermentation a été présentée à un groupe de notables du village, on a choisi une famille pour effectuer la démonstration expérimentale. En même temps que l'on étudiait les besoins énergétiques de cette famille, la disponibilité de matières de base de fermentation, les caractéristiques de l'emplacement et tous autres facteurs pertinents, une unité familiale de type indien modifié a été con?ue et érigée à côté de la ferme. Le composteur, d'un volume utile de matières premières de 9 m³, est relié à la fois aux latrines et à l‘étable. Cette unité fonctionne avec satisfaction depuis le mois de mai 1981. L'article met en avant les points essentiels des étapes de la construction et les caractéristiques de rendement de l'unité de fermentation. Il esquisse une évaluation technico-économique préliminaire et fait l'estimation des retombées sociales. Les premiers résultats montrent que, dans le cadre du village égyptien et particulièrement du fait que les prix du fuel sont largement subventionnés, les économies importantes réalisées dans le transport du fumier grâce á l'introduction de l'unité de fermentation semblent étre, du point de vue du fermier, le bénéfice principal. Dentro del contexto del proyecto de I & D y demostración realizado por el Centro de Investigación Nacional de Egipto, la demostración en los villorrios es de suma importancia. Este artículo presenta un caso pionero de este tipo. Basado en encuestas sociológicas, un villorrio tradicional de Egipto, “Al Manawat” fue selectiondo para la primera demostración. Después de una fase corta de orientación en la que se introdujo la tecnologia del biogás a los representantes del villorrio, se seleccionó una familia con cuya colaboración se Ilevaria a cabo el experimento. Teniendo en cuenta las necesidades de energia de la familia, la disponibilidad de materia prima para el digestor, las caracter ísticas del lugar y otros factores importantes, se diseñó y construyó un digestor de tamaño familiar, usando un modelo Indio, al lado de la casa de la familia. El volumen efectivo del digestor es 9 metros cúbicos y está conectado a la letrina y al corral de animales. La unidad está funcionando con éxito desde Mayo de 1981. Se discuten aspectos de la etapa de construcción y las características de operación. Se hace también una evaluación técnico-económica preliminar. Finalmente se evalúa el impacto social de la experiencia. Los resultados indican que en las condiciones de los villorrios Egipcios, especialmente en condiciones de precios de combustibles altamente sub-sidiados, los grandes ahorros en el transporte de abono debido a la introducción del digestor de biogas parece ser el mayor beneficio desde el punto de vista de la familia.     

A comparison of the persistence in a clay loam of single and repeated annual applications of seven granular insecticides used for corn rootworm control

In May 1983, granular formulations of carbofuran, chlorpyrifos, disulfoton, fonofos, isofenphos, phorate, and terbufos were applied in incorporated bands to duplicate 2 m2 field plots of clay loam. Insecticide concentrations were determined in the bands at 0,1,2,3,4,6,8,10,12,16, and 20 wk. Following spring cultivation, the insecticides were applied to the same plots in 1984 and 1985. In addition, carbofuran was applied to previously untreated plots in 1984 and all 7 materials were applied to previously untreated plots in 1985. Sampling and analysis were carried out as in 1983. Persistence was assessed on the basis of the disappearance rates measured for the 1st 8 wk and of a calculated Effectiveness Potential (the ratio of the average residue in the upper 5 cm of the band at 8, 10 and 12 wk and the published LC95 for western corn rootworm in clay loam soil). Soils treated with carbofuran and isofenphos in 1984 and all soils treated in 1985 were tested for anti-insecticide activity. Soil cores from some carbofuran, chlorpyrifos and terbufos treated plots were sectioned vertically to establish the distribution of the insecticides during 1985. In addition, granular and pure chemical forms of isofenphos and carbofuran were applied at 10 ppm to anti-isofenphos and anti-carbofuran active and control soils (from field plots) maintained at 10 and 20% moisture in the laboratory to assess the effect of formulation and moisture on persistence in active soils. Insecticide concentrations were determined at 0,1,3,7, 10,14,21,28, and 35 days. The persistence of chlorpyrifos, terbufos and phorate was relatively constant over the 3 years and between plots receiving single and multiple treatments. Disulfoton and fonofos behavior was more variable and that of carbofuran and isofenphos was extremely variable. Anti-insecticide activity against carbofuran and isofenphos was detectable 2 wk after an initial application and was still present the following spring. Anti-insecticide activity against fonofos, terbufos sulfoxide, phorate sulfone and disulfoton sulfone was also generated in this soil. Anti-insecticide activity against chlorpyrifos, disulfoton, terbufos and phorate was not present. Carbofuran, chlorpyrifos and terbufos (+ metabolites) present in the upper 5 cm of soil averaged 93, 94 and 94%, respectively, of the total core contents over 12 wk. Significant moisture dependent differences were observed between the behavior of granular carbofuran and granular isofenphos in anti-insecticide active soils.(ABSTRACT TRUNCATED AT 400 WORDS)     

Carbofuran residues in organic soils in Southwestern Ontario, 1977

Organic soils from 22 farms with a history of carbofuran use for soil insect control were sampled in November, 1977. Analysis for carbofuran was by electron capture gas chromatography of the heptaflurobutyric derivative. Nineteen of the 22 soils contained detectable (sensitivity 0.02 ppm) carbofuran residues. However only 8 of the soils contained greater than 0.5 ppm total carbofuran. The highest total carbofuran residue was 1.5 ppm, of which 0.31 ppm was 3-ketocarbofuran. In other soil samples 3-ketocarbofuran comprised 7-50% of the total carbofuran residue. No 3-hydroxycarbofuran was detected. The order of persistence of granular application of 3 insecticides as seed-furrow treatments was ethion greater than fonofos greater than carbofuran.