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Mycotoxin contamination of wheat kernels and diversity of fungal pathogens were monitored in a survey of 26 fields in Nakuru district, Kenya, in 2006. Sampling was performed twice; at mid-anthesis in July for leaves, stems and spikelets and at harvest in September for spikelets and kernels. Kernels were analysed for the occurrence of 32 mycotoxins using a high performance liquid chromatography – electrospray tandem mass spectrometry (LC-ESI-MS/MS) method. Fungi were isolated from surface-sterilized tissues and differentiated morphologically to the genus level. Fusarium isolates were identified based on the sequence of translation elongation factor 1-alpha gene. Eleven Fusarium-related mycotoxins were quantified with deoxynivalenol being detected at highest frequency (69%) and highest concentrations. Occurrence of enniatins in wheat (50%) is reported for the first time in Kenya. Non- Fusarium mycotoxins detected included aflatoxin G2, ochratoxin A, alternariol and alternariol monomethyl ether. Prevalence of Fusarium species on different wheat parts was 100% at both growth stages. Nineteen Fusarium species were identified with seven species – Fusarium chlamydosporum, Fusarium boothi, Fusarium poae, Fusarium scirpi, Fusarium arthrosporioides, Fusarium oxysporum and Fusarium graminearum– accounting for 80% of infections. At anthesis, spikelets and leaves were the most and least susceptible tissue, respectively. At harvest, infection of spikelets was 59% higher than that of kernels. [ABSTRACT FROM AUTHOR]

A reliable and sensitive analytical method for the determination of estrone (E1), 17β- estradiol (E2), and the synthetic hormone 17α-ethinylestradiol (EE2) has been established. Samples are concentrated using automated solid-phase extraction and analysis is performed by liquid chromatography with detection by tandem mass spectrometry. Recoveries of all analytes were between 93% and 107%, and limits of quantification (LOQs) between 0.1 and 0.4 ng/L for purified sewage, and surface, ground, and drinking water, and between 1 and 2 ng/L in case of raw sewage. For the investigation of estrogen release into the environment and its behavior during sewage and surface water treatment, and during ground water recharge, samples from municipal waste water treatment plants (WWTPs), a surface water treatment plant, a bank filtration site, and a ground water enrichment (GWE) pond were analyzed. E1 was found in the raw waste water with an average concentration of 157 ng/L, whereas E2 and EE2 were found with mean concentrations of only 18 and 9 ng/L, respectively. Sewage treatment by municipal WWTPs affected a removal of EE2 (76%), E1 (92%), and E2 (94%). In the investigated surface water of Berlin, only E1 could be detected at concentrations around or below 1 ng/L. E2 and EE2 were not present in the Berlin surface water above the LOQ of 0.2 ng/L, respectively. Surface water treatment also leads to a significant removal of E1 (> 80%). In the ground water samples from the GWE site near Lake Tegel, only a few samples contained detectable concentrations of E1. These samples were collected from a shallow monitoring well located very close to the bank of the pond. Even a short distance between the bank and observation wells led to concentrations of E1 below the LOQ showing the potential of ground water recharge systems for the retention of estrogenic steroids depending on the environmental setting. [ABSTRACT FROM AUTHOR]