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Ward T.J.,ABC Laboratories | Gaertner K.E.,ABC Laboratories | Gaertner K.E.,SynTech Research | Gorsuch J.W.,Copper Development Association Inc | Call D.J.,Environmental Research and Information Analysts
Bulletin of Environmental Contamination and Toxicology | Year: 2015

Juvenile marine polychaetes, Neanthes arenaceodentata, were exposed for 28 days to copper (Cu)-spiked sediment at six concentrations ranging from 48.3 to 2380 mg Cu/kg dry sediment, plus control. Survival was reduced (p ≤ 0.05) at concentrations ≥1190 mg Cu/kg. Growth was inhibited at Cu concentrations ≥506 mg Cu/kg. Dose–response relationships yielded LC10 and LC50 estimates of 514 and 1230 mg Cu/kg, respectively. The growth effect EC50 estimate was 409 mg Cu/kg. Ranges for the no observable effect concentration and lowest observable effect concentration were 506–1190 mg Cu/kg for survival, and 230–506 mg Cu/kg for growth. Pore water concentrations of Cu were 38.7–65.8 µg Cu/L in exposures where toxic effects were observed, compared to a range of 15.1–22.4 µg Cu/L in exposures where significant effects were not evident. The results of the study were compared with empirical and mechanistic sediment quality guidelines for the protection of benthic organisms. © 2015 Springer Science+Business Media New York

Lourenco W.R.,French Natural History Museum | Ythier E.,SynTech Research
ZooKeys | Year: 2010

A new species of the endemic Malagasy genus Pseudouroplectes Lourenc ̧o, 1995 (family Buthidae) is described from spiny forests of the southwestern portion of the island. The holotype was obtained in the forests of Ifaty, north of Toliara. With the description of this species, the distributional pattern of this genus is confined to dry forest formations in the south and southwest. A key is proposed to the known species. © W.R. Lourenço, E. Ythier.

Tozzi E.S.,SynTech Research
American Laboratory | Year: 2012

A correct choice of the probe to purchase, probe capabilities, and limitations should be considered with respect to soil type, location of access tubes, and whether or not continuous monitoring is necessary. The Diviner 2000 and EnviroSCAN are less expensive and are not subject to the regulations and permit requirements imposed on the Hydroprobe. However, the Hydroprobe is extremely durable, reliable, and accurate, which is necessary for many research projects. The Neutron Hydroprobe allows for fairly rapid measurements at discrete depths along a 2.44-m profile, but the Diviner 2000's automatic depth and orientation sensing of the capacitance sensor allows swipe-and-go capabilities that significantly decrease sampling time. The Diviner 2000 and EnviroSCAN rely on capacitance sensors that use frequency domain reflectometry. Since the electrical capacitance of the soil is considered part of the sensor's circuit, the dielectric constant of the soil is determined from the charge time of the capacitor.

Farkas Z.,National Food Chain Safety Office | Horvath Z.,National Food Chain Safety Office | Kerekes K.,National Food Chain Safety Office | Ambrus A.,National Food Chain Safety Office | And 2 more authors.
Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes | Year: 2014

The sampling uncertainty for pesticide residues in carrots, parsley leaves and selected medium size crops was estimated with simple random sampling by applying range statistics. The primary samples taken from treated fields consisted of individual carrots or a handful of parsley leaves. The samples were analysed with QUEChERs extraction method and LCMS/MS detection with practical LOQ of 0.001 mg/kg. The results indicate that the average sampling uncertainties estimated with simple random sampling and range statistics were practically the same. The confidence interval for the estimated sampling uncertainty decreased with the number of replicate samples taken from one lot and the number of lots sampled. The estimated relative ranges of sampling uncertainty are independent from the relative standard deviation of the primary samples. Consequently the conclusions drawn from these experiments are generally applicable. There is no optimum for sample size and number of lots to be tested for estimation of sampling uncertainty. Taking a minimum of 6 replicate samples from at least 8-12 lots is recommended to obtain a relative 95% range of sampling uncertainty within 50%. The cost of sampling/analyses, the consequences of wrong decision should also be taken into account when a sampling plan is prepared. © 2014 Copyright Taylor and Francis Group, LLC.

Lourenco W.R.,French Natural History Museum | Ythier E.,SynTech Research
ZooKeys | Year: 2013

A new species of Tityus, subgenus Atreus (Scorpiones: Buthidae) is described from the Province of Pichincha in the Ecuadorian Andes. Ecuadorian scorpion fauna remains one of the less well studied among those of South America. Nevertheless, some comments are addressed about its remarkable diversity and high level of endemic elements. © Wilson R. Lourenço, Eric Ythier.

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