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The effects of plastic related phthalates (DEHP) upon ragworm, Hediste diversicolor

Alnemari, Ashwaq M.


Ashwaq M. Alnemari


Jörg D. Hardege

Thomas Breithaupt


The exposure of the general public to phthalates is widespread as well as quite variable. Many human consumer products consist of a range of phthalates as ingredients of plastic materials. These include building materials, clothing, household furniture, cosmetics, pharmaceuticals, medical equipment, dentures, nutritional supplements, food packaging materials, children toys, modeling clay, waxes, glow sticks, cleaning materials, lubricants, automobile parts and also some insecticides (Schettler, 2005).
Animals are exposed in their natural habitats to a variety of human activities including those related to dissolved chemicals that are released into aquatic systems and may impact their fitness and survival. The responses of animals to stress, generated by these chemicals, determines their biochemical and behavioural fitness. Phthalate esters are example of such chemicals. Di-2-ethylhexyl phthalate (DEHP) and Hediste diversicolor were used for the purpose of this study. Hediste diversicolor were exposed to various low concentrations of 0.05, 2, and 10 μg/L of DEHP in long term exposures (3 months), and to high concentrations of 100, and 500 μg/L DEHP in short term exposure studies (7 days). The study aims to provide evidence that the accumulation of DEHP in H. diversicolor results in changes to their behaviours, specifically feeding and burrowing activity, as well as changes in their biochemical responses to phthalate driven oxidative stress via catalase and superoxide dismutase enzymes. DEHP showed different levels of persistence in seawater depending on concentrations. DEHP accumulated significantly more in H. diversicolor and persisted also in the sediment, while it degraded quickly in seawater. Exposure to DEHP generated behavioural impairments in H. diversicolor in the form of a decrease in the feeding time and an increase in the burrowing time, a typical predator escape behaviour. In addition to this stressed worm also showed an increase in two biomarkers of oxidative-stress, CAT enzymes and stability in SOD enzymes. Field samples showed fluctuations of DEHP over the year and significant differences in DEHP levels between various locations in the Humber Estuary, but generally DEHP levels are significantly higher in H. diversicolor followed by the sediment and seawater.


Alnemari, A. M. (2018). The effects of plastic related phthalates (DEHP) upon ragworm, Hediste diversicolor. (Thesis). University of Hull. Retrieved from

Thesis Type Thesis
Deposit Date Jan 5, 2023
Publicly Available Date Feb 24, 2023
Keywords Biological sciences
Public URL
Additional Information Department of Biological Sciences, The University of Hull
Award Date Sep 1, 2018


Thesis (4.6 Mb)

Copyright Statement
© 2018 Alnemari, Ashwaq M. All rights reserved. No part of this publication may be reproduced without the written permission of the copyright holder.

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