Surveys of rice sold in Canada for aflatoxins, ochratoxin A and fumonisins

Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid Chromatographic methods in two different years. The mean concentrations for aflatoxin B1 (AFB1) were 0.19 and 0.17 ng g−1 with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g−1). Twenty-three samples analysed in the second year also contained aflatoxin B2 (AFB2) at levels ≥LOD of 0.002 ng g−1 The five most contaminated samples in each year contained 1.44–7.14 ng AFB1 g−1 (year 1) and 1.45–3.48 ng AFB1 g−1 (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g−1 in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g−1 were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B1 (FB1) averaged 4.5 ng g−1 in 15 positive samples (≥0.7 ng g−1) from year 1 (n = 99); fumonisin B2 (FB2) and fumonisin B3 (FB3) were also present (≥1 ng g−1). In the second year there was only one positive sample (14 ng g−1 FB1) out of 100 analysed. All positive FB1 results were confirmed by LC-MS/MS

Immunomagnetic microbeads for screening with flow cytometry and identification with nano-liquid chromatography mass spectrometry of ochratoxins in wheat and cereal

Multi-analyte binding assays for rapid screening of food contaminants require mass spectrometric identification of compound(s) in suspect samples. An optimal combination is obtained when the same bioreagents are used in both methods; moreover, miniaturisation is important because of the high costs of bioreagents. A concept is demonstrated using superparamagnetic microbeads coated with monoclonal antibodies (Mabs) in a novel direct inhibition flow cytometric immunoassay (FCIA) plus immunoaffinity isolation prior to identification by nano-liquid chromatography–quadrupole time-of-flight-mass spectrometry (nano-LC-Q-ToF-MS). As a model system, the mycotoxin ochratoxin A (OTA) and cross-reacting mycotoxin analogues were analysed in wheat and cereal samples, after a simple extraction, using the FCIA with anti-OTA Mabs. The limit of detection for OTA was 0.15 ng/g, which is far below the lowest maximum level of 3 ng/g established by the European Union. In the immunomagnetic isolation method, a 350-times-higher amount of beads was used to trap ochratoxins from sample extracts. Following a wash step, bound ochratoxins were dissociated from the Mabs using a small volume of acidified acetonitrile/water (2/8 v/v) prior to separation plus identification with nano-LC-Q-ToF-MS. In screened suspect naturally contaminated samples, OTA and its non-chlorinated analogue ochratoxin B were successfully identified by full scan accurate mass spectrometry as a proof of concept for identification of unknown but cross-reacting emerging mycotoxins. Due to the miniaturisation and bioaffinity isolation, this concept might be applicable for the use of other and more expensive bioreagents such as transport proteins and receptors for screening and identification of known and unknown (or masked) emerging food contaminants

Assessing Gaps and Poverty-Related Inequalities in the Public and Private Sector Family Planning Supply Environment of Urban Nigeria

Nigeria is the most populous country in Africa, and its population is expected to double in <25 years (Central Intelligence Agency 2012; Fotso et al. 2011). Over half of the population already lives in an urban area, and by 2050, that proportion will increase to three quarters (United Nations, Department of Economic and Social Affairs, Population Division 2012; Measurement Learning & Evaluation Project, Nigerian Urban Reproductive Health Initiative, National Population Commission 2012). Reducing unwanted and unplanned pregnancies through reliable access to high-quality modern contraceptives, especially among the urban poor, could make a major contribution to moderating population growth and improving the livelihood of urban residents. This study uses facility census data to create and assign aggregate-level family planning (FP) supply index scores to 19 local government areas (LGAs) across six selected cities of Nigeria. It then explores the relationships between public and private sector FP services and determines whether contraceptive access and availability in either sector is correlated with community-level wealth. Data show pronounced variability in contraceptive access and availability across LGAs in both sectors, with a positive correlation between public sector and private sector supply environments and only localized associations between the FP supply environments and poverty. These results will be useful for program planners and policy makers to improve equal access to contraception through the expansion or redistribution of services in focused urban areas

Final reading outcomes of the national randomized field trial of Success for All

Using a cluster randomization design, schools were randomly assigned to implement Success for All, a comprehensive reading reform model, or control methods. This article reports final literacy outcomes for a 3-year longitudinal sample of children who participated in the treatment or control condition from kindergarten through second grade and a combined longitudinal and in-mover student sample, both of which were nested within 35 schools. Hierarchical linear model analyses of all three outcomes for both samples revealed statistically significant school-level effects of treatment assignment as large as one third of a standard deviation. The results correspond with the Success for All program theory, which emphasizes both comprehensive school-level reform and targeted student-level achievement effects through a multi-year sequencing of literacy instruction

Do Trees Grow with the Economy? A Spatial Analysis of the Determinants of Forest Cover Change in Sichuan, China

China, Economic growth, Environmental Kuznets Curve, Forest resources, Remote sensing, Spatial econometrics,