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Higher temperatures expected in a future warmer climate could adversely affect the growth and development of mosquitoes. This study investigated the effects of elevated temperatures on longevity, gonotrophic cycle length, biting rate, fecundity, and body size of Anopheles gambiae (s.l.)(Diptera: Culicidae) mosquitoes. Anopheles gambiae (s.l.)eggs obtained from laboratory established colonies were reared under eight temperature regimes (25, 28, 30, 32, 34, 36, 38, and 40°C), and 80 ± 10% RH. All adults were allowed to feed on a 10% sugar solution soaked in cotton wool; however, some mosquitoes were provided blood meal using guinea pig. Longevity was estimated for both blood-fed and non-blood-fed mosquitoes and analyzed using the Kaplan–Meier survival analysis. One-way ANOVA was used to test the effect of temperature on gonotrophic cycle length, biting rate, and fecundity. Adult measurement data were log-transformed and analyzed using ordinary least square regression with robust standard errors. Increasing temperature significantly decreased the longevity of both blood-fed (Log-rank test; X2(4) = 904.15, P< 0.001) and non-blood-fed (Log-rank test; X2(4) = 1163.60, P< 0.001) mosquitoes. In addition, the fecundity of mosquitoes decreased significantly (ANOVA; F(2,57) = 3.46, P= 0.038) with an increase in temperature. Body size (β = 0.14, 95% CI, 0.16, 0.12, P< 0.001) and proboscis length (β = 0.13, 95% CI, 0.17, 0.09, P <0.001) significantly decreased with increasing temperature from 25 to 34°C. Increased temperatures expected in a future warmer climate could cause some unexpected effects on mosquitoes by directly influencing population dynamics and malaria transmission.

This review compiles information on PCDD/F- and PCB-contaminated eggs from 20 years of global egg monitoring around emission sources in four continents conducted by the International Pollutants Elimination Network (IPEN) and Arnika as well as a compilation of data from scientific literature. IPEN monitored 127 pooled egg samples including samples from 113 chicken flocks at potential PCDD/F- and PCB-contaminated sites around priority sources listed in the Stockholm Convention (e.g. waste incinerators, metal industries, cement plants, and open burning). 99 (88%) of pooled egg samples were above the EU maximum limits for PCDD/Fs (2.5 pg PCDD/F-TEQ/g fat) or the sum of PCDD/Fs and dioxin-like PCBs (5 pg PCDD/F-PCB-TEQ/g fat). Children consuming such eggs exceed the tolerable weekly intake (TWI). This demonstrates that close to 90% of these areas were not safe for the production of free-range eggs. Sixteen out of the 113 egg samples (14%) were contaminated above 50 pg TEQ/g fat and exceeded the EU maximum limit more than 10 times. From the 26 pooled egg samples around incinerators 24 (92%) exceeded the limit with a mean of 43.1 pg TEQ/g fat (2.6–234 pg TEQ/g). All 21 egg samples around metal industries (4.4–112.6 pg TEQ/g fat) were above limits with mean concentration of 26.0 pg TEQ/g fat. Also all 7 egg samples measured at e-waste recycling sites were above limits (mean 308 pg TEQ/g fat). In 58 (51%) pooled egg samples the PCB-TEQ was above 5 pg TEQ/g fat exceeding the EU maximum limit with dioxin-like PCBs alone. This highlights the role of commercial PCBs for global contamination with dioxin-like compounds. It was discovered that around metal industries, shredder plants, open burning sites of e-waste and dump sites, a high share of contamination was caused by dl-PCBs. This clearly shows severe PCB release from the end-of-life management of PCB-containing equipment in developing countries. Also highly contaminated eggs were found at many sites where plastic was incinerated. The highest contaminated egg sample ever measured came from an e-waste site in Ghana and had 856 pg TEQ/g fat plus 300 pg TEQ from brominated dioxins (PBDD/Fs). Other extreme PCDD/F contaminations of eggs were found at a chlor-alkali site (514 pg TEQ/g fat), Agent Orange contaminated areas in Vietnam (490, 249 and 246 pg TEQ/g fat) and e-waste sites (568 and 520 pg TEQ/g fat). Where DR CALUX® bioassay revealed higher TEQ compared to measured PCDD/F-PCB-TEQ in IPEN studies, polybrominated PBDD/F were also measured and detected up to 300 pg TEQ/g fat at e-waste sites. One positive outcome from the IPEN studies is that all 10 pooled supermarket eggs in developing countries were below regulatory limit. Policy recommendations are made including: a systematic assessment of areas around PCDD/Fs and PCBs sources; measures for reduction of exposures of populations; urgent control of emission sources including PCB equipment, the open burning of plastic, and the use of plastic as fuel in boilers/incinerators in developing countries without air pollution control. Furthermore, soil limits need to be re-assessed and lowered for free-range poultry.

Access to useful climate information is critical for adaptation needs of African smallholder farmers, yet empirical studies documenting the socioeconomic, environmental and household predictors of access to and willingness to pay for climate information services from a gendered perspective have been limited to date. This paper addresses this research need by identifying the predictors of access to and willingness to pay for climate information by smallholder farmers in north-eastern Ghana, a “vulnerability hotspot” where slight changes in rainfall often result in considerable yield losses. The study uses data collected from 193 household surveys in 2 communities across 2 districts in the Upper East region of Ghana. The logit regression was performed based on a disaggregated procedure. Our findings suggest that the majority of smallholder farmers were not willing to pay for the cost of receiving climate information. Results show that only 50% (n = 121) of the male farmers compared with just 31% (n = 72) of female farmers were willing to pay for climate information. The results from the marginal analysis suggest that access to climate information is influenced by both household and environmental factors. The marginal effects logistic regression shows statistically significant differences in the predictors of access and willingness to pay for climate information based on gender. Findings highlight that the provision of climate information should be designed and tailored to meet the needs of smallholder farmers with different socioeconomic backgrounds to enable farmers manage climate risks and build adaptive capacity. The Ghana Meteorological Agency needs to be supported through capacity building on communication to provide targeted climate information for farmers in this climate “vulnerability hotspot”.