Abstract
This study aimed to analyze the ecotoxicity of nitrogen-, phosphorus-, and potassium-based compounds to organisms of two different trophic levels in order to compare the toxic effect between high-purity substances and these substances as components of fertilizers. Dilutions were made with the fertilizers’ potassium chloride, potassium nitrate, superphosphate, urea, and their equivalent reagents, to conduct assays to establish the acute lethal concentration for half of the population (LC50). Ten individuals of the benthic snail Biomphalaria glabrata and the fish Danio rerio were exposed to each concentration of tested compounds. As a result, the toxicity levels of potassium chloride, potassium nitrate, and urea were obtained for B. glabrata and D. rerio, with the fish being more susceptible to potassium chloride in the fertilizer and the snail to potassium nitrate and urea, in both commercial and reagent forms. Regarding superphosphate, no significant toxicity was found. This study concluded that among the tested substances, KNO3 and KCl were the most toxic substances and urea the least toxic. It was not possible to establish the most sensitive species since, for KCl, the fish were more susceptible to the fertilizer and the snail to the reagent, while for KNO3 the opposite was observed.
Highlights
Within the agricultural production chain, nitrogen (N), potassium (K), and phosphorus (P) are of great importance for the practice of agriculture
Given the results presented here, it can be concluded that the fertilizers KCl, KNO3, and urea have toxic effects on B. glabrata and D. rerio, with the zebrafish being more susceptible to KCl present in fertilizer and the snail to the other compounds
Faced with the data presented, it can be concluded that KCl, KNO3, and urea fertilizers have acute toxic effects on B. glabrata and D. rerio
Summary
Within the agricultural production chain, nitrogen (N), potassium (K), and phosphorus (P) are of great importance for the practice of agriculture. In the production process it is difficult for the farmer to obtain a high yield without using at least phosphate-, nitrogen-, and potassium-based fertilizers. According to the International Fertilizer Industry Association [1], on average 104,252 million tons of nitrogen, 40,522 million tons of phosphate, and 27,435 million tons of potassium are used each season worldwide. Nitrogen, when in aqueous medium, is converted into ammonia, nitrite, and nitrate in a three-step process [2]. It is known that of these three ions, ammonia is the most toxic to aquatic organisms [3], but these compounds often exist at low concentrations in aquatic ecosystems because they are the main source of nitrogen for primary producers [4].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
