0
Article Tier 2 Human Health Effects Sign in to save

Polystyrene microplastics enhanced the toxicity of cadmium to rice seedlings: Evidence from rice growth, physiology, and element metabolism

The Science of The Total Environment 2024 20 citations

AI summary Read the abstract

Polystyrene microplastics combined with cadmium -- a toxic heavy metal -- caused more damage to rice seedlings than either pollutant alone, reducing growth and disrupting the balance of essential nutrients. At higher concentrations, the microplastics significantly increased how much cadmium the plants absorbed into their above-ground parts. This matters for human health because rice is a staple food for billions of people, and microplastic-contaminated farmland could lead to higher heavy metal levels in the food supply.

Polymers

Microplastics (MPs) and cadmium (Cd) are toxic to rice; however, the effects and mechanisms of their combined exposure are unclear. The combined exposure effects of polystyrene microplastics (PS-MPs) with different particle sizes (1-10 μm, 50-150 μm) and concentrations (50, 500 mg·L) and Cd on rice were explored. PS-MPs combined with Cd amplifies the inhibition of each individual exposure on the height and biomass of rice seedlings, and they showed antagonistic effects. PS-MPs reduced the content of chlorophyll and increased the content of carotenoid rice seedlings significantly. High concentrations of PS-MPs enhanced the inhibition of Cd on chlorophyll content. Cd, PS-MPs single and combined exposures significantly altered the antioxidant enzyme (POD, CAT, SOD) activities in rice seedlings. Under PS-MPs exposure, overall, the MDA content in shoots and roots exhibited opposite trends, with a decrease in the former and an increase in the latter. In comparison with Cd treatment, the combined exposures' shoot and root MDA content was reduced. Cd and PS-MPs showed "low concentration antagonism, high concentration synergism" on the composite physiological indexes of rice seedlings. PS-MPs significantly increased the Cd accumulation in shoots. PS-MPs promoted the root absorption of Cd at 50 mg·L while inhibited at 500 mg·L. Cd and PS-MPs treatments interfered with the balance of microelements (Mn, Zn, Fe, Cu, B, Mo) and macroelements (S, P, K, Mg, Ca) in rice seedlings; Mn was significantly inhibited. PS-MPs can enhance of Cd's toxicity to rice seedlings. The combined toxic effects of the two contaminants appear to be antagonistic or synergistic, relying on the particle size and concentration of the PS-MPs. Our findings offer information to help people understanding the combined toxicity of Cd and MPs on crops.

More Papers Like This

Article Tier 2

Phenotypic and Physiological Responses of Rice Seedlings to Co-Exposure of Polystyrene Microplastics and Heavy Metals

AI summary Read the abstract

Scientists found that microplastics in soil don't just add their own contamination risk to crops like rice, they can actually change how toxic heavy metals like lead and cadmium affect the plant, making cadmium's harm milder but making lead's harm worse. This matters because farmland is increasingly exposed to both microplastics and heavy metal pollution together, and this study suggests we can't predict crop safety by looking at these contaminants separately, their combined effects are more complex and need further research to understand how they might impact the food we eat.

Article Tier 2

Exploration of Single and Co-Toxic Effects of Polypropylene Micro-Plastics and Cadmium on Rice (Oryza sativa L.)

AI summary Read the abstract

Researchers investigated the single and combined toxic effects of polypropylene microplastics and cadmium on rice plants, finding that co-exposure altered cadmium bioavailability and produced compounded negative effects on plant growth and development.

Article Tier 2

Microplastic–Cadmium Interaction in Paddy Soils: An Overlooked Risk Exacerbating Cadmium Contamination in Rice and Microbial Dysbiosis

AI summary Read the abstract

Scientists found that tiny plastic particles in rice paddies make it easier for the toxic metal cadmium to get into rice plants, leading to more contamination in the rice we eat. When microplastics and cadmium are both present in flooded rice fields, rice plants grow less and absorb significantly more of the harmful metal compared to when only cadmium is present. This matters because cadmium can cause serious health problems like kidney damage and cancer, so this research suggests that plastic pollution may be making our rice less safe to eat.

Article Tier 2

Oxidative Damage in Roots of Rice (Oryza sativa L.) Seedlings Exposed to Microplastics or Combined with Cadmium

AI summary Read the abstract

Rice seedlings exposed to polystyrene microplastics and cadmium showed combined toxic effects on root growth, fresh and dry weight, and antioxidant enzyme activities, with combined exposure producing greater oxidative damage than either pollutant alone. The study highlights synergistic phytotoxicity in a staple crop relevant to food security in microplastic-contaminated paddy soils.

Article Tier 2

Polystyrene nanoplastics distinctly impact cadmium uptake and toxicity in Arabidopsis thaliana

AI summary Read the abstract

In a study using the model plant Arabidopsis, polystyrene nanoplastics increased the uptake and accumulation of the toxic heavy metal cadmium in plant roots. The combined stress of nanoplastics and cadmium caused worse oxidative damage and growth problems than either pollutant alone. This is concerning because it means microplastics in agricultural soil could help toxic metals get into crops more easily, potentially increasing human exposure through food.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper