Hazardous Chemicals in Plastics in Marine Environments : International Pellet Watch
Yamashita, Rei ; Tanaka, Kosuke ; Yeo, Bee Geok ; Takada, Hideshige ; Franeker, Jan A. van; Dalton, Megan ; Dale, Eric - \ 2019
In: Hazardous Chemicals Associated with Plastics in the Marine Environment Springer Verlag (Handbook of Environmental Chemistry ) - ISBN 9783319955667 - p. 163 - 183.
Additives - Equilibrium - Open ocean - Pellets - Sorption
Marine plastic debris, including microplastics <5Â mm, contain additives as well as hydrophobic chemicals sorbed from surrounding seawater. A volunteer-based global monitoring programme entitled International Pellet Watch (IPW) is utilizing the sorptive nature of plastics, more specifically of beached polyethylene (PE) pellets, in order to measure persistent organic pollutants (POPs) throughout the world. Spatial patterns of polychlorinated biphenyls (PCBs) and organochlorine pesticides have been revealed. Original data of IPW show large piece-to-piece variability in PCB concentrations in pellets collected at each location. This is explained by the combination of slow sorption/desorption and large variabilities of speed and route of floating plastics. The sporadically high concentrations of POPs, both sorbed chemicals and hydrophobic additives, are frequently observed in pellets and the other microplastics in open ocean and remote islands. This poses a chemical threat to marine ecosystems in remote areas.
Efficiency of additives and internal physical chemical factors for pit latrine lifetime extension
Grolle, Katja ; Ensink, Jeroen ; Gibson, Walter ; Torondel, Belen ; Zeeman, Grietje - \ 2018
Waterlines 37 (2018)3. - ISSN 0262-8104 - p. 207 - 228.
Additives - Human faeces - Pit latrines - Solids hydrolysis
Pit latrines are the most common form of on-site sanitation, but are blighted by the problem of pit fill-up. Little is known about what factors and conditions affect decomposition of pit content and thus govern pit filling, but the liquid-mass balance is the key factor. Under laboratory conditions the effect of inorganic and biological additives and the effect of physical chemical factors on solids hydrolysis of black water and human faeces were investigated to establish the potential of these to extend pit latrine lifetime. Additives did little or nothing to enhance net solids hydrolysis in batch tests or to reduce pit fill height in miniature simulated pit latrines. Physical chemical factors such as redox condition and initial pH increased solids hydrolysis, whereas temperature and substrate moisture did little. Since additives need contact with the substrate to act, measurements on faeces crust formation speed and strength were performed and showed that crusts formed within three hours and persisted after covering with fresh faeces or water.
Early-stage sustainability assessment to assist with material selection : a case study for biobased printer panels
Broeren, M.L.M. ; Molenveld, K. ; Oever, M.J.A. van den; Patel, M.K. ; Worrell, E. ; Shen, L. - \ 2016
Journal of Cleaner Production 135 (2016). - ISSN 0959-6526 - p. 30 - 41.
Additives - Biobased - Bioplastics - Design - Life cycle assessment - Material selection
This paper aims to incorporate sustainability assessment into the material selection processes during early-stage product (re)design, when time and data availability for such assessments are usually limited. A material selection framework is presented and illustrated step-by-step with a case study aiming to identify biobased alternatives for petrochemical plastics used for (flame retardant) panels. After an initial screening step, the technical performance of selected materials is measured. A cradle-to-grave screening life cycle assessment compares the environmental performance of the candidate and reference materials on greenhouse gas emissions, non-renewable energy use and agricultural land use per kilogram. A simplified cost analysis is performed. The environmental and economic indicators are corrected for each candidate's technical performance by estimating expected weight changes in the final product based on material indices. In this case study, two biobased plastics are found to offer equal or improved environmental/economic performance compared to reference materials. Furthermore, the case study shows that additive production can significantly contribute to the plastics' environmental impacts, e.g. accounting for 5–40% of their cradle-to-grave greenhouse gas emissions. The case study demonstrated that the proposed materials selection framework is a useful tool for early-stage product design.