Table 1.
Studies assessing the synergetic/antagonistic effect of inorganic pollutants combined with MPs.
| MP Type | MP Size | Chemical Sorbate | Exposure Concentrations * | Exposure Time |
Organism | Toxicological Assessment | Highlight Results | Ref. |
|---|---|---|---|---|---|---|---|---|
| PS | Average diameter: 201.5 nm | Nickel |
Ni alone [Ni] = 1, 2, 3, 4, and 5 mg/L MPs alone [MPs] = 1,5,10,20,30 mg/L Variable Ni-Fixed MPs [Ni] = 1, 2, 3, 4, and 5 mg/L [MPs]= 5 mg/L Fixed Ni-Variable MPs [Ni] = 3 mg/L [MPs] = 1,5,10,20,30 mg/L Variable Ni-Variable MPs 1 mg/L Ni-1 mg/L MP 2 mg/L Ni-5 mg/ L MP 5 mg/L Ni-30 mg/L MP |
48 h | Daphnia magna | Rate of abnormalities and changes in the morphology Rate of immobilization |
Enhanced toxicity of Ni in combination with both MPs Higher immobilization effect for Ni - PS-COOH exposure Ni showed an antagonistic effect on toxicity with PS and synergistic with PS-COOH Results may indicate that the toxic effects of MPs and Ni vary depending of the properties of both pollutants |
[120] |
| PS-COOH | Average diameter: 191.3 nm | |||||||
| PE | 1–5 µm | Chromium (VI) |
Cr (VI) alone [Cr (VI)] = 0, 5.6, 8.4, 12.6, 18.9 and 28.4 mg/L MPs alone [MPs]= 0.184 mg/L MPs + Cr (VI) Co-exposure performed using the same concentrations of single treatments |
96 h | Early juveniles of the common goby fish (Pomatoschistus microps) | Post-predatory performance assay The activities of AChE, GST, EROD activities LPO levels |
Significant decrease of the predatory performance and significant inhibition of AChE activity under simultaneous exposure Long-term exposure to different environmental conditions in developmental phases influences the response of early juveniles |
[121] |
| PS | 32–40 µm | Cadmium |
Cd alone [Cd]= 0 and 50 µg/L MPs alone [MPs]= 0, 50, 500 µg/L MPs + Cd 3 × 2 array configuration (MPs previously preloaded with Cd for 24 h before the exposure experiments) |
30 days | Early juveniles of discus fish (Symphysodon aequifasciatus) | Survival rate Body length The activities of SOD, CAT, GPx, LZM, ACP and ALP The level of GSH and C3 The concentrations of MDA and PC |
The MP + Cd mixture induced severe oxidative damage as well as the stimulation of the immune system Co-exposure stimulate the innate immune responses of early juveniles |
[122] |
| PS | 5 µm | Cadmium |
Cd alone [Cd]= 10 µg/L MPs + Cd 10 µg/L Cd-20 µg/L MPs 10 µg/L Cd-200 µg/L MPs (MPs incubated during 96h before the exposure experiments) |
3 weeks | Zebrafish (Danio rerio) |
Histological analysis (liver, gut and gills) GSH and MT levels SOD activity mRNA levels of 8 target genes in zebrafish tissues |
Enhanced toxicity of Cd in combination with MPs Oxidative stress and early inflammatory responses observed in the mixture treatments Important changes in the gene expression observed for all co-exposure treatments |
[123] |
| unknown | 1–5 µm | Mercury |
Hg alone [Hg]= 0.010 and 0.016 mg/L MPs alone [MPs]= 0.26 and 0.69 mg/L MPs + Hg 4 binary mixtures using the same concentrations of single exposures |
96 h | Juvenile European seabass (Dicentrarchus labrax) | AChE, ChE, IDH and LDH activities LPO levels |
A significant interaction between MPs and Hg was achieved Biomarkers’ variation was highly influenced by the concentration of MPs |
[124] |
| unknown | 1–5 µm | Mercury |
Hg alone [Hg] = 30 µg/L MPs alone [MPs] = 0.13 mg/L MPs + Hg Co-exposure performed using the same concentrations of single treatments |
8 days (+ 6 days in clean medium) |
Freshwater bivalve (Corbicula fluminea) | The post-exposure filtration rate ChE, IDH, GST, GSR, GPx, ODH and CAT activities LPO levels |
Antagonistic behaviour between MPs and Hg in several biomarkers Six days of post-exposure recovery in the clean medium was not enough to reverse the toxic effects induced by both pollutants |
[125] |
| PE | 10–45 µm | Mercury |
Hg alone [Hg] = 10 µg/L MPs alone [MPs] = 25 µg/L MPs + Hg Co-exposure and incubation treatments performed using the same concentrations of single treatments (incubation for 96h) |
7 days | Manila clam (Ruditapes philippinarum) | Histological analysis (gill and digestive gland) Filtration rates Immunomodulation Oxidative stress |
The filtration rates decreased as a result of the co-exposure A higher decrease in haemocyte viability was detected in co-exposure treatments Antioxidant parameters remain unchanged in the mixture in comparison to single treatments |
[7] |
| PE | 1–5 µm | Copper |
Cu alone [Cu]= 0.02, 0.04, 0.08, 0.16, 0.32 and 0.64 mg/L MPs alone [MPs] = 0.046, 0.092, 0.184, 0.368, 0.736 and 1.472 mg/L MPs + Cu 6 binary mixtures using the same concentrations of Cu combined with 0.184 mg/L of MPs |
96 h | Marine microalgae (Tetraselmis chuii) | The average specific growth rate and the percentage of growth inhibition | No significant differences were observed between treatments with and without MPs MPs did not influence the Cu toxicity |
[119] |
| Virgin PVC | D50: 139 µm | Copper |
Cu alone [Cu]= 0, 0.2, 0.5 and 1 mg/L MPs alone (virgin and aged) [MPs] = 10, 100 and 1000 mg/L MPs + Cu 0.5 mg/L Cu-10 mg/L aged MPs |
10 days | Microalgae (Chlorella vulgaris) | The growth inhibition ratio (IR) and biomass productivity The enzymatic activities of SOD and MDA |
Mixture exposure enhances the cell growth in comparison to single treatments The ageing of MPs poses stronger inhibitory effects in microalgae than virgin pellets |
[92] |
| Aged PVC | D50:132 µm | |||||||
| PS | 0.1 µm 20 µm |
Copper |
Cu alone [Cu] = 50 µg/L MPs alone [MPs] = 200 µg/L MPs + Cu Combination of concentrations used in single treatments |
14 days | Zebrafish (Danio rerio) | SOD, MDA and MT levels Transcriptomic analysis |
Synergetic effects in co-exposure treatments of small MPs were observed The presence of MPs and DOM aggravates the Cu-toxicity |
[102] |
* Shadowed cells represent environmental relevant concentrations.