Removal of tetracycline by natural and iron-modified orange peel from aqueous solutions: processes in batch, column, and mechanism.

Natural (OP) and iron modified orange peel (Fe-OP) were used for the removal of tetracycline from aqueous solutions in batch and fixed bed column systems. The adsorbents were characterized by infrared spectroscopy (IR) and the morphologies of the surfaces before and after tetracycline removal were determined by scanning electron microscope and the elemental analysis was performed by X-ray dispersive spectroscopy (EDS). The kinetic behaviour showed that the equilibrium was reached in 24 and 10 h for OP and Fe-OP respectively, the data were adjusted to both the pseudo second order and intraparticle diffusion models which indicate a chemisorption mechanism and the adsorption process is controlled by the intraparticle diffusion process. The isotherms showed that the adsorption capacity was eight times higher for Fe-OP than OP and the data were best fitted to the Freundlich model indicating that the materials are heterogeneous. The effect of flow rate, influent concentration and adsorbent mass were determined in the column system. The data were adjusted to the Thomas, Adams-Bohart and Yoon-Nelson models, and the best adjustment of data was with the first one. The adsorption capacities in the column system were about half of those obtained in the batch system. These adsorbents show good properties for the removal of tetracycline from water.

Effects of dietary supplementation with organic selenium-enriched yeast on growth performance, carcass characteristics, and meat quality of finishing lambs.

This study was aimed to assess the impact-enriched Saccharomyces cerevisiae with organic selenium addition in finishing lambs on fatty acid composition and physicochemical meat characteristics. Eighteen five-month-old Pelibuey female lambs were fed the same diet for 60 days. Animals were assigned a completely random design of three treatments, control (Se0) without the addition of selenium-yeast or supplemented with 0.35 ppm of selenium-yeast (Se35) and with 0.60 ppm of selenium-yeast (Se60). Lambs were slaughtered at an average weight of 39.5 ± 4.41 kg. Feed intake and meat water holding capacity were decreased (P = 0.001) in Se35 lambs, whereas meat moisture and fat were decreased (P = 0.002) in Se60 lambs. However, meat carbohydrates were increased (P = 0.001) in Se60 lambs. It is concluded that consumption of selenium-yeast in lambs did not alter the productive variables nor the fatty acid composition, though, the fat content is lower, and the carbohydrates are higher in physicochemical meat characteristics.

Prenatal exposure to phthalates is associated with decreased anogenital distance and penile size in male newborns.

Reproductive effects from phthalate exposure have been documented mostly in animal studies. This study explored the association between prenatal exposure to phthalate metabolites, anogenital distance and penile measurements in male newborns in Toluca, State of Mexico. A total of 174 pregnant women provided urine samples for phthalate analysis during their last prenatal visit, and the 73 who gave birth to male infants were included in the study. The 73 male newborns were weighed and measured using standardized methods after delivery. After adjusting for creatinine and supine length at birth, significant inverse associations were observed between an index of prenatal exposure to total phthalate exposure and the distance from the anus to anterior base of the penis (ß = -0.191 mm per 1 µg/l, P = 0.037), penile width (ß = -0.0414, P = 0.050) and stretched length (ß = -0.2137, P = 0.034); prenatal exposure to mono-2-ethylhexyl phthalate exposure was associated with a reduction in the stretched length of the penis (ß = -0.2604, P = 0.050). Human exposure to phthalates is a public health concern, and the system most vulnerable to its potential effects seems to be the immature male reproductive tract.

Exposición prenatal a ftalatos. Anemia materna, duración de la gestación y somatometría del recién nacido / Prenatal exposure to phthalates. Maternal anemia, pregnancy duration and neonatal somatometry

Los ésteres del ácido ftálico conocidos comúnmente como ftalatos son contaminantes ubicuos existentes en alimentos, aire, suelo, sedimentos, productos de belleza y materiales de construcción a los que las mujeres embarazadas se encuentran expuestas. Exposiciones previas de ftalatos durante la fecundación pueden producir mayor riesgo de efectos adversos por contacto de la madre con estos. Muchas sustancias químicas pueden atravesar la placenta y llegar al embrión en el periodo de mayor diferenciación, pueden acumularse en los tejidos corporales y liberarse al torrente sanguíneo, para de esta manera producir un daño en el proceso de gestación. El objeto del presente estudio fue identificar la asociación de la presencia de metabolitos de ftalatos con efectos adversos en el embarazo. El promedio del grupo de edad fue de 21,3±4,4 años, los recién nacidos tuvieron un peso de 2.927±490g, la presencia del metabolito monobenzil ftalato predominó en el 53,13% de las muestras, las fuentes de exposición a ftalatos son: jabón y crema en 93,7% y desodorante en 90,6%. El dimetil ftalato (DMP) se asoció con anemia con una p<0,01; el DMP se asoció a la disminución de la edad gestacional con p<0,04, el monobutil ftalato (MBP) se asoció a recién nacidos del sexo femenino con p<0,01, la presencia de monobutil ftalato se asocia a la disminución del perímetro cefálico, torácico y abdominal así como al peso de los recién nacidos con diferencias estadísticamente significativas (AU)

Phthalic acid esters, commonly known as phthalates, are ubiquitous pollutants in foods, air, ground, sediments, beauty products and construction materials to which pregnant women are exposed. Previous phthalate exposure during fertilization can increase the risk of undesired effects through maternal contact with these esters. Many chemical substances can cross the placenta and reach the embryo in the period of greatest differentiation. These substances accumulate in body tissues and are then released into the bloodstream, thus producing harmful effects in the pregnancy. The aim of the present study was to identify the association between the presence of phthalate metabolites and adverse effects in pregnancy. The mean maternal age was 21.3±4.4 years. The mean birthweight was 2927±490 grams. Monobenzyl phthalate metabolite predominated in 53.13% of the samples. Sources of phthalate exposure were soap and cream in 93.7% and deodorant in 90.6%. Dimethyl phthalate was associated with anemia (P<0.01) and decreased gestational age (P<0.04). Mono butyl phthalate was associated with female sex in the neonate (P<0.01), decreased head, chest and abdominal circumference and lower birthweight, with statistically significant differences (AU)

Removal of methyl parathion in water, by Dugesia dorotocephala.

The aim of this study was to determine the efficiency of Dugesia dorotocephala on Methyl parathion removal. An initial concentration of 1.25 microg mL(-1) of MeP was used to evaluate the removal capacity of planarian. A first-order removal kinetics was obtained with a disappearance rate constant (k(r)) of 0.49 days(-1) and 69% efficiency on contaminant removal. This is significantly different (p < 0.5) from the degradation occurring in control systems, leading us to conclude that D. dorotocephala effectively removes MeP from contaminated water.

Determination of DNA damage in floriculturists exposed to mixtures of pesticides.

The aim of the study was to determine possible DNA damage in floriculturists chronically exposed to pesticides. Leukocytes from 52 workers, 46 environmentally exposed, and 38 control individuals were evaluated with the comet assay. Serum from all individuals was also analyzed for pesticides using gas chromatography coupled to mass spectrometry. A statistically significant difference in DNA fragmentation in the pesticide exposed group compared to the other two groups (P < .001) was found. No differences between environmentally exposed and control individuals were detected. The statistical analysis showed no significant correlation between DNA damage and sex, age, drinking or smoking habits, as well as years of exposure. One or more pesticides were detected in 50% of the floriculturists, while in the rest of the individuals, a chemical related with the preparation of pesticides, such as additives, plasticizers, or solvents, was found. Our study shows that chronic exposure to pesticides produces DNA damage in floriculturists. It also suggests that this type of monitoring could be valuable in recommending preventive measures.