Track topics on Twitter Track topics that are important to you
This study investigated the effect of surface charge on the sorption of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS) onto 7 tropical soils as a function of pH. The net surface charge became less negative with decreasing pH (from 7.5 to 3.5) in all soils. The rate of change in net surface charge varied from -0.6 to -2.8 (cmol/kg)/pH unit. The effect on sorption behaviour of PFASs was variable among soils. For two soils, the average sorption increased 54- and 45-fold for PFOS, 33- and 9-fold for PFOA, and 39- and 400-fold for PFHxS, across the pH range 7.5 to 3.5. Sorption in another sandier soil showed negligible change with decreasing pH. Sorption in the other soils did not change significantly until the pH decreased to approximately 5.5. The soils with high contents of sesquioxides (Fe and Al oxides) showed the most marked increase in sorption with decreasing pH. This study demonstrated that in addition to hydrophobic interactions with OC and other processes, electrostatic interactions are also important in the sorption process for these chemicals in soils. In acidic, variably charged tropical soils there is the possibility that any PFOS, PFOA or PFHxS sorbed to the soils may become desorbed if management practices (e.g. liming) raised soil pH.
This article was published in the following journal.
Name: The Science of the total environment
6:2 chlorinated polyfluorinated ether sulfonate (trade name F-53B), a perfluorooctane sulfonate alternative used as a mist suppressant in the chromium plating industry, is environmentally persistent a...
This research studied the sorption behavior of uranium(VI) onto two different kinds of soils: surface soil and undersurface soil that taken from the depth of 30 m undersurface. The soil samples were...
The influence of K+ and Ca2+ on the sorption of nonionic aromatic contaminants (1,4-dinitrobenzene and p-xylene) on a series of microporous zeolite minerals (HZSM-5) with various surface charge densit...
We study dispersion of a charged solute in a charged micro- and nanochannel with reversible sorption and derive an analytical solution for mass fraction in the fluid, transport velocity and dispersion...
Studies that deal with iodine mobility in uncontaminated agricultural soils are scarce and unique. Therefore, in this article, we have evaluated the sorption behavior of two most abundant naturally oc...
Tropical diseases are continuously on the rise throughout the world as they are spreading and manifesting in various locations globally. The more prominent vector tends to be the mosquito ...
This study will investigate the relationship between sedentary behaviour and subjective well-being among a sample of university students. Eligible participants will fill out an online surv...
Severe dry eye is a debilitating ocular disease resulting in loss of vision, reduced day-to-day function and significant discomfort. Tear substitutes are an important part of the treatment...
This is a pilot study of intervention in a group of patients with tropical spastic paraparesis/ myelopathy to evaluate virologic and clinical response of raltegravir plus zidovudine in thi...
The purpose of this study is to determine the efficacy of 2 different doses of intramuscular vitamin D3 as compared to an oral replacement dose in normalizing vitamin D levels in the blood...
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
Non-frontal low-pressure systems over tropical or sub-tropical waters with organized convection and definite pattern of surface wind circulation.
A form of elephantiasis caused by soil particles which penetrate the skin of the foot. It is limited to tropical regions with soils of high volcanic content.
Rare disease characterized by COLOBOMA; CHOANAL ATRESIA; and abnormal SEMICIRCULAR CANALS. Mutations in CHD7 protein resulting in disturbed neural crest development are associated with CHARGE Syndrome.
The branch of medicine concerned with diseases, mainly of parasitic origin, common in tropical and subtropical regions.
Tropical Medicine is the study of diseases more commonly found in tropical regions than elsewhere. Examples of these diseases are malaria, yellow fever, Chagas disease, Dengue, Helminths, African trypanosomiasis, Leishmaniasis, Leprosy, Lymphatic filaria...