Fixed-bed adsorption of pesticide agricultural waste using cross-linked adsorptive hydrogel composite beads.

Adsorption column blockage due to solid adsorbent material is prevalent in laboratory-scale applications. Creating composite materials with stable geometries offers a viable solution. By crafting hydrogel beads using sodium alginate (Alg) and a bio-source like activated carbon (RMCA-P), it becomes possible to effectively eliminate agricultural pollutants, including the pesticide 2,4-D, from aqueous solutions. To evaluate the performance of these beads, a range of structural and textural analyses such as DRX, FTIR, SEM/EDX, BET, Zeta potential, Boehm titration, and iodine number were employed. Moreover, the study found that optimizing certain parameters greatly enhanced adsorption column efficiency. Specifically, increasing the bed height while reducing the flow rate of the adsorbate and the initial concentration in the inlet proved beneficial. The column demonstrated peak performance at a flow rate of 0.5 mL/min, a bed height of 35 cm, and an inlet adsorbate concentration of 50 mg/L. Under these conditions, the highest recorded removal rate for 2,4-D was 95.49%, which was subsequently confirmed experimentally at 95.05%. Both the Thomas and Yoon-Nelson models exhibited a good fit with the breakthrough curves. After undergoing three cycles of reuse, the RMCA-P/Alg hydrogel composite maintained a 2,4-D removal percentage of 74.21%. Notably, the RMCA-P/Alg beads exhibited effective removal of 2,4-D from herbicidal field waters in a continuous operational mode.

First External Quality Assessment of Molecular and Serological Detection of Rift Valley Fever in the Western Mediterranean Region.

Rift Valley fever (RVF) is a mosquito-borne viral zoonosis which affects humans and a wide range of domestic and wild ruminants. The large spread of RVF in Africa and its potential to emerge beyond its geographic range requires the development of surveillance strategies to promptly detect the disease outbreaks in order to implement efficient control measures, which could prevent the widespread of the virus to humans. The Animal Health Mediterranean Network (REMESA) linking some Northern African countries as Algeria, Egypt, Libya, Mauritania, Morocco, Tunisia with Southern European ones as France, Italy, Portugal and Spain aims at improving the animal health in the Western Mediterranean Region since 2009. In this context, a first assessment of the diagnostic capacities of the laboratories involved in the RVF surveillance was performed. The first proficiency testing (external quality assessment--EQA) for the detection of the viral genome and antibodies of RVF virus (RVFV) was carried out from October 2013 to February 2014. Ten laboratories participated from 6 different countries (4 from North Africa and 2 from Europe). Six laboratories participated in the ring trial for both viral RNA and antibodies detection methods, while four laboratories participated exclusively in the antibodies detection ring trial. For the EQA targeting the viral RNA detection methods 5 out of 6 laboratories reported 100% of correct results. One laboratory misidentified 2 positive samples as negative and 3 positive samples as doubtful indicating a need for corrective actions. For the EQA targeting IgG and IgM antibodies methods 9 out of the 10 laboratories reported 100% of correct results, whilst one laboratory reported all correct results except one false-positive. These two ring trials provide evidence that most of the participating laboratories are capable to detect RVF antibodies and viral RNA thus recognizing RVF infection in affected ruminants with the diagnostic methods currently available.

Contents of cadmium, mercury and lead in fish from the Atlantic sea (Morocco) determined by atomic absorption spectrometry.

As a part of a specific monitoring program, lead (Pb) cadmium (Cd) and mercury (Hg) concentrations in important species of fish from various fishing ports of the southern Kingdom of Morocco (Sardina pilchardus, Scomber scombrus, Plectorhinchus mediterraneus, Trachurus trachurus, Octopus vulgaris, Boops boops, Sarda sarda, Trisopterus capelanus, and Conger conger) were investigated by the Moroccan Reference Laboratory (NRL) for trace elements in foodstuffs of animal origin. The samples were analysed for lead and cadmium by a graphite furnace atomic absorption spectrometry (GFAAS); and for mercury by cold vapour atomic absorption spectrometry (CVAAS). The results were expressed as µg/g of wet weight (w/w). The levels of Cd, Pb and Hg in muscles of fish were 0.009-0.036, 0.013-0.114 and 0.049-0.194 µg/g, respectively. The present study showed that different metals were present in the sample at different levels but within the maximum residual levels prescribed by the EU for the fish and shellfish from these areas, in general, should cause no health problems for consumers.