Detection and quantitative analysis of 21 veterinary drugs in river water using high-pressure liquid chromatography coupled to tandem mass spectrometry

Introduction

The use of veterinary drugs in food production focuses on the control and improvement of animal health. The disadvantage of this practice is that pharmaceuticals and their metabolites are released into the environment, finding their way to natural water systems and becoming a potential risk to non-target organism.

Methods

This paper reports the development and validation of a quantitative method, based on high-performance liquid chromatography coupled to tandem mass spectrometry, for the simultaneous analysis of 21 veterinary drugs, antimicrobials, corticosteroids, coccidiostats and antifungal agents, in surface water.

Results

The precision of the method was established by calculating the mean recoveries, which were in the range of 94?C101%. The developed method was employed to conduct the first monitoring study on the presence of veterinary drugs in the Galicia region, Northwest of Spain and was applied to 235 surface water samples. Eleven veterinary drugs were detected at concentrations from below the limit of quantification to 2,978.6?ng?L^?1. Limits of detection and quantification were in the range of 6.2 (betamethasone, cortisone, decoquinate, dexamethasone, maduramycin, monensin, narasin, salinomycin, sulfachloropyridazine, sulfamethoxypyridazine and trimethoprim) to 12.5?ng?L^?1 (for the rest of the selected drugs) and 12.5 (betamethasone, cortisone, decoquinate, dexamethasone, maduramycin, monensin, narasin, salinomycin, sulfachloropyridazine, sulfamethoxypyridazine and trimethoprim) to 25.0?ng?L^?1 (for the remaining pharmaceuticals), respectively.

Conclusion

Sulfonamides were the group most frequently found, which are widely used in veterinary medicine.     

A study on toxic and essential elements in rice from the Republic of Kazakhstan: comparing the level of contamination in rice from the European Community

Selected toxic elements (total As, Cd, Cr, Hg, Pb, Sr, U and V) and essential elements (Co, Cu, Fe, Mn and Zn) were analyzed using an inductively coupled plasma mass spectrometry (ICP-MS) in unpolished and milled rice collected from Kazakhstan and milled rice from Spain and Portugal to evaluate the potential health risk to the population. Arsenic species (arsenite, arsenate, arsenobetaine, dimethylarsinate and monomethilarsonate) were analyzed using HPLC-IC-MS. From 146 samples analyzed, none of them exceeded the maximum limit set by the European Legislation for Cd or Pb or values recommended by the Codex Alimentarius. Concentrations of Sr, U and V were below LOD and those of Hg, Pb, Co and Cr between <LOD and 0.54 mg/kg (highest concentration of Cr) in milled rice. Portuguese rice samples contained the highest mean concentration of As, Hg, Pb, Co, Cr, Cu, Mn and Zn. The highest mean of arsenobetaine (0.001 mg/kg), dimethylarsinate (0.27 mg/kg) and monomethilarsonate (0.02 mg/kg) was found in Spanish rice and that of arsenite (0.30 mg/kg) in Kazakh rice. Inorganic As in samples from Kazakhstan was above the ML (0.2 mg/kg) proposed by FAO/WHO, but in seven samples from Spain and in four from Portugal were above the limit. The estimated weekly intake of total or inorganic As(III, V), Cd, Hg and Pb for rice consumption by Kazakh, Spanish and Portuguese adults and children was lower than the provisional tolerable weekly intake established by Joint FAO/WHO Expert Committee on Food Additives and the European Food Safety Authority.

     

Detection of veterinary drug residues in surface waters collected nearby farming areas in Galicia,North of Spain

The occurrence of pharmaceuticals in the aquatic environment has become a matter of concern in the last decade due to potential risks posed to non-target organisms and the potential for unintended human exposure via food chain. This concern has been driven by a high detection frequency for drugs in environmental samples; these substances are produced in large quantities and are used in both veterinary and human medicine, leading to deposition and potential effects in the environment. However, few studies have focused on the presence of pharmaceuticals in rural areas associated with farming activities in comparison to urban areas. The aim of this study is to investigate the occurrence of pharmaceutically active compounds in surface waters collected from urban and rural areas in northwestern Spain. A monitoring study was conducted with 312 river water samples analysed by high-performance liquid chromatography coupled to tandem mass spectrometry. Positive detection of pharmaceuticals was made for 51 % of the samples. Decoquinate, sulfamethazine, sulfamethoxypyridazine and trimethoprim were the drugs most frequently detected, being present in more than 10 % of the samples. The sampling sites located downstream of the discharge points for wastewater treatment plants yielded the highest number of positive samples, 13 % of the positive samples were detected in these sites and 38 % of the samples collected near the collection point of a drinking water treatment plant were positive.     

Temperature enhanced effects of chlorine exposure on the health status of the sentinel organism Mytilus galloprovincialis

It now is widely recognised that the global temperature is rising, a phenomenon which could alter the effects of pollution on wildlife. In order to assess the role of temperature and exposure to chlorine due to cooling water discharges, a battery of metabolic, oxidative stress and histological parameters were evaluated in Mytilus galloprovincialis after 15 and 30 days at 15 °C and at two increased temperatures (+5 and +10 °C). Diverse gill pathologies such as haemolymphatic sinus dilatation, an increased number of mucocytes and granulocytes as well as a lower number of cilia were observed after 30 days exposure at higher temperatures. Protein, amino acid, triglyceride and fatty acid levels decreased when the temperature increased, as a consequence of higher energetic demand. Similarly, acetylcholinesterase, catalase and glutathione S-transferase activities showed an inhibition at higher temperatures, although gill lipid peroxidation levels remained unaffected. Our results suggest that increased temperatures induce deterioration in the health status of the mussels and in their defensive capacity against a polluted environment.     

PM composition and source reconciliation in Mexico City

PM_2.5 and PM₁₀ were collected during 24-h sampling intervals from March 1st to 31st, 2006 during the MILAGRO campaign carried out in Mexico City's northern region, in order to determine their chemical composition, oxidative activity and the estimation of the source contributions during the sampling period by means of the chemical mass balance (CMB) receptor model. PM_2.5 concentrations ranged from 32 to 70 μg m⁻³ while that of PM10 did so from 51 to 132 μg m⁻³. The most abundant chemical species for both PM fractions were: OC, EC, SO₄²⁻, NO₃⁻, NH₄⁺, Si, Fe and Ca. The majority of the PM mass was comprised of carbon, up to about 52% and 30% of the PM2.5 and PM10, respectively. PM2.5 constituted more than 50% of PM10. The redox activity, assessed by the dithiothreitol (DTT) assay, was greater for PM_2.5 than for PM₁₀, and did not display significant differences during the sampling period. The PM_2.5 source reconciliation showed that in average, vehicle exhaust emissions were its most important source in an urban site with a 42% contribution, followed by re-suspended dust with 26%, secondary inorganic aerosols with 11%, and industrial emissions and food cooking with 10% each. These results had a good agreement with the Emission Inventory. In average, the greater mass concentration occurred during O₃S that corresponds to a wind shift initially with transport to the South but moving back to the North. Taken together these results show that PM chemical composition, oxidative potential, and source contribution is influenced by the meteorological conditions.