The potential use of non-viable biomass of a Gram negative bacterium i.e. Acinetobacter haemolyticus to remove Cr(III) species from aqueous environment was investigated. Highest Cr(III) removal of 198.80 mg g(-1) was obtained at pH 5, biomass dosage of 15 mg cell dry weight, initial Cr(III) of 100 mg L(-1) and 30 min of contact time. The Langmuir and Freundlich models fit the experimental data (R(2)>0.95) while the kinetic data was best described using the pseudo second-order kinetic model (R(2)>0.99). Cr(III) was successfully recovered from the bacterial biomass using either 1M of CH(3)COOH, HNO(3) or H(2)SO(4) with 90% recovery. TEM and FTIR suggested the involvement of amine, carboxyl, hydroxyl and phosphate groups during the biosorption of Cr(III) onto the cell surface of A. haemolyticus. A. haemolyticus was also capable to remove 79.87 mg g(-1) Cr(III) (around 22.75%) from raw leather tanning wastewater. This study demonstrates the potential of using A. haemolyticus as biosorbent to remove Cr(III) from both synthetic and industrial wastewater.
The prevalence of asthma is increasing, especially among children in Malaysia, with environmental factors as one of the main preventable contributors. The aim of this study was to determine the association between environmental air pollutants and the occurrence of asthma among children seen in pediatric clinics in Universiti Kebangsaan Malaysia Medical Center (UKMMC), Kuala Lumpur. An unmatched case control study among children who attended the pediatric clinic was carried out from May to August 2015. A total of 223 children who were diagnosed with asthma (105 cases) and who did not have asthma (118 controls) were included in this study. Their parents or caregivers were interviewed using questionnaires modified from the International Study of Asthma and Allergies in Childhood. Data obtained were analyzed using SPSS software version 20. There was a higher risk of asthma in those who had carpet at home (OR = 2.15 CI [1.25-3.68]), those who lived within 200 m of heavy traffic (OR = 1.72 CI [1.01-2.93]), and those who were exposed to lorry fumes (OR = 2.61. CI [1.38-4.93]). Environmental air pollutants increased the risk of asthma among children in Malaysia. Exposure to congested roads, lorry fumes, and indoor carpet were associated with asthma among children in this study. Parents or caretakers of children with asthma should be given adequate education on the prevention of asthmatic attack among these children.
Study site: Paediatric clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia