Geochemical Characterization and Mineralogical Assemblage of Burhi-Dihing and Noa-Dihing – The Largest South Bank Tributaries of the Brahmaputra River

Author: Aparna Das, Sumi Handique, Monalisa Chaowlu and Manish Kumar
Year of Publication: 2018
Published: Asian Journal of Water, Environment and Pollution 13(4): 13-24.

Mineralogical studies are valuable in understanding past weathering regimes induced by changing climatic conditions. Information about the bedrock lithology, weathering regimes, erosion and sedimentation rates are fundamental issues for better understanding of the river catchment behaviours. In this context, therefore, major ions, trace metals and clay mineral compositions of the sediment and water of Noa-Dihing and Burhi-Dihing rivers, the southbank tributaries of the Brahmaputra river, have been examined. Chemical index of alteration (CIA) values of both Noa-Dihing and Burhi-Dihing rivers suggests the prevalence of moderate chemical weathering events and formation of minerals such as muscovite, illite and smectite in the river catchment. Metal distribution in both rivers shows highly toxic metals, comprised of 32% of total mineral composition, and are less abundant with respect to moderately toxic metals (37%) except Zr, which comprises 37% and 32% respectively of the total mineral compositions. Comparison of sediment chemistry with composition of source rocks and average Upper Continental Crust (UCC) suggests higher depletion of CaO, Na2O, P2O5, Al2O3, SiO2, MgO and MnO signifying the dominance of mafic mineral phases. Loss of these metal oxides from the bed rocks during weathering and/or less abundance of clay in bed sediments compared to that in UCC may also be attributed to depleted values of these minerals. This is further substantiated by grain size analysis i.e. more abundance of sandy silt as compared to clay minerals in the overbank and channel sediments of Noa-Dihing and Burhi-Dihing rivers. Chemical Index of Alteration (CIA) varies significantly from 64.49 to 81.21, indicating large spatial variability in the intensity of chemical weathering of upper Brahmaputra basin. Multivariate analysis suggests that natural weathering processes of alkaline earth metals can be associated with release of trace metals in a riverine system and releasing mechanism of transition metal and their oxides are same and that of alkali and alkaline earth metal are similar.

Geochemistry, Mineralogy, Noa-Dihing, Burhi-Dihing, Grain size analysis, X-ray diffraction, Cluster analysis

Das, A., Handique, S., Chaowlu, M., Kumar, M. (2016): Geochemical Characterization and Mineralogical Assemblage of Burhi-Dihing and Noa-Dihing—The Largest South Bank Tributaries of the Brahmaputra River. Asian Journal of Water, Environment and Pollution 13(4): 13-24.


Tezpur University, India

Project name:
To study the sediment geochemistry of the Brahmaputra River

Project description:
To study the surface water geochemistry of the Brahmaputra river as well as the suspended sediment geochemistry. Understanding the mechanism of weathering and erosion processes affecting the geochemistry of the surface water and quantification of denudation rates in the Brahmaputra river.

Fate of microplastics in wastewater treatment plants and their environmental dispersion with effluent and sludge

Author: Carlos Edo, Miguel González-Pleiter, Francisco Leganés, Francisca Fernández-Piñas and Roberto Rosal
Year of Publication: 2020
Published: Environmental Pollution

This work studied the occurrence of microplastics in primary and secondary effluents and mixed sludge of a WWTP as well as in processed heat-dried sludge marketed as soil amendment. Sampled microparticles were divided into fragments and fibres, the latter defined as those with cylindrical shape and length to diameter ratio >3. We showed the presence of 12 different anthropogenic polymers or groups of polymers with a predominance of polyethylene, polypropylene, polyester and acrylic fibres together with an important amount of manufactured natural fibres. The smaller sampled fraction, in the 25–104 μm range, was the largest in both primary and secondary effluents. Fibres displayed lower sizes than fragments and represented less than one third of the anthropogenic particles sampled in effluents but up to 84% of heat-dried sludge. The plant showed a high efficiency (>90%) in removing microplastics from wastewater. However, the amount of anthropogenic plastics debris in the 25 μm – 50 mm range still released with the effluent amounted to 12.8 ± 6.3 particles/L, representing 300 million plastic debris per day and an approximate load of microplastics of 350 particles/m3 in the receiving Henares River. WWTP mixed sludge contained 183 ± 84 particles/g while heat-dried sludge bore 165 ± 37 particles/g. The sludge of the WWTP sampled in this work, would disseminate 8 × 1011 plastic particles per year if improperly managed. The agricultural use of sludge as soil amendment in the area of Madrid could spread up to 1013 microplastic particles in agricultural soils per year.

Microplastics, wastewater treatment plants, sewage sludge, wastewater effluent, removal efficiency

Edo, C., González-Pleiter, M., Leganés, F:, Fernández-Piñas, F., Rosal, R. (2020): Fate of microplastics in wastewater treatment plants and their environmental dispersion with effluent and sludge. Environmental Pollution.


Secondary nanoplastics released from a biodegradable microplastic severely impact freshwater environments

Author: Miguel González-Pleiter, Miguel Tamayo-Belda, Gerardo Pulido-Reyes, Georgiana Amariei, Francisco Leganés, Roberto Rosal and Francisca Fernández-Piñas
Year of Publication: 2019
Published: Environmental Science: Nano

Over the last five decades, plastics production has increased as a consequence of their use in strategic sectors causing damage on aquatic ecosystems. In this context, biodegradable plastics have emerged as an ecological alternative because they are easily degradable in the environment. Despite the recent advances in the field of plastic ecotoxicology, the ecological impact of secondary nanoplastics (nanoplastics resulting from natural degradation of micro and macro plastics) in the environment remains poorly understood. Here, we have investigated the effects of secondary nanoplastics of polyhydroxybutyrate (PHB), a biodegradable plastic, on three representative organisms of aquatic ecosystems. Secondary PHB-nanoplastics were produced from PHB-microplastics by abiotic degradation under environmentally representative conditions. Secondary PHB-nanoplastics induced a significant decrease in cellular growth and altered relevant physiological parameters in all organisms. We investigated whether the observed toxicity was exerted by PHB-nanoplastics themselves or by other abiotic degradation products released from PHB-microplastics. An experiment was run in which PHB-nanoplastics were removed by ultrafiltration; the resulting supernatant was not toxic to the organisms, ruling out the presence of toxic chemicals in the PHB-microplastics. In addition, we have performed a complete physicochemical characterization confirming the presence of secondary PHB-nanoplastics in the 75–200 nm range. All results put together indicated that secondary PHB-nanoplastics released as a consequence of abiotic degradation of PHB-microplastics were harmful for the tested organisms, suggesting that biodegradable plastic does not mean safe for the environment in the case of PHB.

Nanoplastic, biodegradable microplastic, freshwater environments

González-Pleiter, M., Tamayo-Belda, M., Pulido-Reyes, G., Amariei, G., Leganés, F., Rosal, R., Fernández-Piñas, F. (2020): Secondary nanoplastics released from a biodegradable microplastic severely impact freshwater environments. Environmental Science: Nano 2019 (6): 1382 – 1392


Occurrence and identification of microplastics along a beach in the Biosphere Reserve of Lanzarote

Author: Carlos Edo, Miguel Tamayo-Belda, Sergio Martínez-Campos, Keila Martín-Betancor, Miguel González-Pleiter, Gerardo Pulido-Reyes, Carmen García-Ruiza, Félix Zapata, Francisco Leganés, Francisca Fernández-Piñas and Roberto Rosal
Year of Publication: 2019
Published: Marine Pollution Bulletin

This work studied the accumulation of plastic debris in a remote beach located in La Graciosa island (Chinijo archipelago, Canary Islands). Microplastics were sampled in the 1–5 mm mesh opening range. An average plastic density of 36.3 g/m² was obtained with a large variability along the 90 m of the beach (from 8.5 g/m² to 103.4 g/m²). Microplastic particles preferentially accumulated in the part of the beach protected by rocks. A total number of 9149 plastic particles were collected, recorded and measured, 87% of which corresponded to fragments. Clear colours and microscopic evidence of weathering corresponded to aged plastics wind-driven by the surface Canary Current. The chemical composition of plastics particles corresponded to PE (63%), PP (32%) and PS (3%). Higher PE/PP ratios were recorded in the more protected parts of the beach, suggesting preferential accumulation of more aged fragments.

Marine debris, marine pollution, microplastics, FTIR, Raman

Edo, C., Tamayo-Belda, M., Martínez-Campos, D., Martín-Betancor, K., González-Pleiter, M., Pulido-Reyes, G., García-Ruiza, C., Zapata, F., Leganés, F., Fernández-Piñas, F., Rosal, R. (2019): Occurrence and identification of microplastics along a beach in the Biosphere Reserve of Lanzarote. Marine Pollution Bulletin 143:220–227


Universidad Autonoma de Madrid

Project name:
Environmental risk of micro and nanoplastics in wastewater treatment systems and receiving bodies

Project description:
Microplastics have long been recognized as environmental pollutants causing impacts to marine and terrestrial life. Microplastics decompose and break up into smaller plastic debris under the action of microbiological and physicochemical degradation processes leading to nanomaterials. Nanoplastics, like other nanomaterials, have unique properties due to their size, shape and their capacity to interact with other substances due to their large surface area. Nanoplastics can produce physical damage but they may also be transported across cell membranes and persist in the environment due to their relative inertness. The chemical composition of plastics makes them a conveyor for non-polar anthropogenic pollutants supposing an additional risk factor for which very little is known.

This proposal aims at providing the information required to evaluate the risk posed by nanoplastics to freshwater ecosystems with particular attention to the processes of fragmentation and environmental transformation in real world scenarios. We will also study the role of micro and nanoplastics as vectors for other pollutants and, for the case of larger particles, as habitats for microbial communities growing on them as biofilms. In particular, we will investigate the damage to organisms naturally exposed to nanoplastics in the receiving bodies of wastewater discharge. The toxicity of nanoplastics to photosynthetic microorganisms will be combined with protozoa and invertebrates representing three trophic levels. Special attention will be paid to the mechanisms of nanoplastic internalization and to their toxic action by using a battery of fluorochromes as indicators of cytotoxicity, cell viability, oxidative and genotoxic damages.

University of Alcalá, Spain

Participating institutions:

  • Universidad de Alcalá (coordinator)
  • Spanish Astrobiology Center, INTA-CSIC
  • Institut de Ciències del Mar, CSIC
  • Instituto Español de Oceanografía, IEO
  • Madrid Institute for Advanced Studies, IMDEA-Water
  • National Institute for Agricultural and Food Research and Technology, INIA
  • Universidad Autónoma de Madrid
  • Universidad de La Laguna
  • Universidad de Las Palmas de Gran Canaria
  • Universidad de Málaga
  • Universidad Nacional de Educación a Distancia
  • Universidad Politécnica de Cartagena
  • Universidade de A Coruña
  • Universidade de Vigo

Project name:
Thematic Newtork of Micro- and Nanoplastics in the Environment (EnviroPlaNet)

Project description:
EnviroPlaNet Thematic Network is an interdisciplinary project coordinating fifteen Spanish research teams working on issues related to the contamination by plastic debris. The objective is to improve coordination in critical key aspects such as the definition of sampling procedures, sample analysis or the development of consistent toxicological and ecotoxicological assessment methodologies. The network includes teams with a prolonged expertise in marine research and the damage to wildlife, fisheries and touristic industry caused by the accumulation of plastic debris in the environment. Other groups focus on risks derived from the generation of smaller fragments, namely micro- and nanoplastics, the leaching of plastics additives or the chemical risk caused by the adsorption of hydrophobic pollutants. The dissemination of microorganisms associated to the plastisphere is another hot topic covered by several teams in the Network. In addition, the Network is granting researchers access to techniques available in other institutions, thereby strengthening the competitive position of participating groups and associated partners. Collaboration instruments include an internal communication structure, research staff training activities such as collaboration in scientific campaigns, and the preparation of publishable materials. Attention is paid to promoting the participation of the different groups in national and international networks and consortia. The Network also promotes knowledge transfer to companies and regulators, as well as to NGOs, policy makers and other social agents. Communication and dissemination activities are being carried out through multiple channels including specialized platforms, scientific dissemination events, and the use of social networks.

Published articles (pdf, 76KB)

15 PhD positions (f/m/d) in the EU Horizon 2020 Marie-Skłodowska-Curie Project: MSCA-ITN-ETN LimnoPlast


“LimnoPlast – Microplastics in Europe’s freshwater ecosystems: From sources to solutions” is funded by the European Commission under the Horizon 2020 programme (Marie Skłodowska-Curie Actions Innovative Training Network) and offers 15 fully funded PhD positions (for early-stage researcher (ESR)) with attractive complementary training activities and generous travel, laboratory and research budgets. The successful candidates will be hosted by a member of a European Consortium of universities, research institutions and companies in Germany, Denmark, France, Slovenia, Norway, Sweden, United Kingdom and The Netherlands. Successful candidates will have a research interest in natural, environmental, technical or social-science and will participate in a transdisciplinary network of research and training aimed at accelerating the applicants’ scientific careers.

LimnoPlast will for the first time bring together environmental, technical, and social sciences with the vision to transform a new understanding of freshwater microplastics to innovative solutions.

LimnoPlast will:

  • Train a new type of scientists (ESRs) able to tackle the complex plastics issue holistically and contribute to Europe’s innovation and Circular Economy capacity. Working at the interface of three usually very distant disciplines, they will promote a step change in how we deal with this and future environmental challenges.
  • Provide the first comprehensive assessment of the sources and impacts of freshwater MP based on the analysis of three major urban areas as hotspots of plastic pollution.
  • Innovate technological solutions to the plastics issue, including novel processes to remove MP from municipal and industrial wastewater as well as bio-degradable, environmentally sound polymers.
  • Promote societal change by understanding the economic, legislative and social context of freshwater MP.
  • Transform science into a set of specific solutions, including (I) the prioritization of actions based on the sources and impacts of MP, development of (II) better processes and polymers, (III) risk communication strategies and societal interventions, (IV) effective policy and legislative interventions.
  • Transfer the LimnoPlast outcomes to European decision makers, stakeholders and the public to enable and promote action on freshwater MP using an innovative communication and dissemination strategy.

Titles of the ESR-projects:

  1. Biological effects of microplastics from biodegradable plastics in freshwater invertebrates.
  2. Development and characterization of novel biodegradable polymers.
  3. Source tracking of microplastics at Aarhus.
  4. Monitoring and modelling microplastics in the greater Paris and the river Seine; pollutants associated with microplastics.
  5. Electrostatic separation of nanoplastics from wastewater.
  6. A socio-ecological assessment for microplastics to address the needs of future Circular Economy in Europe.
  7. Legal situation of microplastics in Europe’s freshwater ecosystems.
  8. Chemistry and bulk properties and degradation of microplastics.
  9. Ecotoxicology of different shapes of microplastics in freshwater invertebrates.
  10. Chemical toxicity of conventional and new plastics.
  11. Microplastics assessment in wasterwater treatment plant – occurrence, removal and fate.
  12. Chronic toxicity of microplastics in fish species.
  13. Risk perceptions and mental models regarding microplastics in freshwater systems and solutions.
  14. Behavioural approaches to the microplastics problem and potential solutions.
  15. From freshwater to drinking water and food-human exposure to microplastics.

More Information:

Environmental variables and benthic macroinvertebrate assemblage in the headwater streams of an Afro-tropical reservoir

Author: Emmanuel O. Akindele and Godwin O. Olutona
Year of Publication: 2015
Published: Water and Environment Journal 29(4): 541-548.

The assemblage of benthic macroinvertebrates in relation to some selected environmental variables of the two headwater streams of Aiba Reservoir was studied from May 2013 to March 2014. This was with a view to assessing the health status and water quality of the streams, and comparing their taxa richness with similar studies on the reservoir and its out‐flowing stream. A total of 23 taxa were recorded in the study. and showed indirect relationships (P < 0.05) with bioindicators of good water quality, while dissolved oxygen (DO) showed indirect relationship (P < 0.05) with bioindicators of poor water quality. The streams were of poor biological water quality, and diversity indices revealed that they were polluted and unstable in habitat structure. Anthropogenic impacts at the upper reaches need to be mitigated and regular biomonitoring of the streams is of the essence, in order to conserve the integrity of the downstream reservoir.

Biodiversity, Conservation, Environmental variables, Headwaters, Macroinvertebrates, Reservoir, Stream, Water quality

Akindele, E.O., Olutona, G.O., 2015. Environmental variables and benthic macroinvertebrate assemblage in the headwater streams of an Afro-tropical reservoir. Water and Environment Journal 29(4): 541-548.


Obafemi Awolowo University, Ile-Ife, Nigeria

Project name:
Microplastic pollution study in the Ogun and Osun River Systems, Nigeria

Project description:
Rivers Osun and Ogun are the two major rivers in the southwestern part of Nigeria and both are tributaries of the Gulf of Guinea within the Nigerian territory. River Osun takes its source from Ekiti State and finally flows into the Lekki Lagoon which is interconnected with the Lagos Lagoon. River Ogun flows from Oyo State into the Lagos Lagoon, and is ultimately linked with the Gulf of Guinea. The project aims at assessing microplastic occurrence and load in the water column and river bed of the both rivers. Sampling will be conducted over a period of time such that it covers the major seasons in Nigeria (e.g. early rainy season, late rainy season, early dry season, late dry season). Samples will be collected for both water and sediment analysis from different sections of the river, as well as in some key indicator macroinvertebrate species. Thereafter, appropriate laboratory techniques will be employed to extract microplastics from the samples, and final identification will be carried out using the micro Fourier Transform-Infrared (µFT-IR) spectroscopy.