Altered Larval Yellow Perch Swimming Behavior Due to Methylmercury and PCB126 Detected Using Hidden Markov Chain Models

Abstract

Fish swimming behavior is a commonly measured response in aquatic ecotoxicology because behavior is considered a whole organism-level effect that integrates many sensory systems. Recent advancements in animal behavior models, such as hidden Markov chain models (HMM), suggest an improved analytical approach for toxicology. Using both new and traditional approaches, we examined the sublethal effects of PCB126 and methylmercury on yellow perch (YP) larvae (Perca flavescens) using three doses. Both approaches indicate larvae increase activity after exposure to either chemical. The middle methylmercury-dosed larvae showed multiple altered behavior patterns. First, larvae had a general increase in activity, typically performing more behavior states, more time swimming, and more swimming bouts per second. Second, when larvae were in a slow or medium swimming state, these larvae tended to switch between these states more often. Third, larvae swam slower during the swimming bouts. The upper PCB126-dosed larvae exhibited a higher proportion and a fast swimming state, but the total time spent swimming fast decreased. The middle PCB126-dosed larvae transitioned from fast to slow swimming states less often than the control larvae. These results indicate that developmental exposure to very low doses of these neurotoxicants alters YP larvae overall swimming behaviors, suggesting neurodevelopment alteration.

Boric Acid Functional Fluorescent Covalent–Organic Framework for Sensitive and Selective Visualization of CH3Hg+

“…The conventional inorganic mercury species can be easily transformed into more toxic methylmercury species by environmental microorganisms . Lipid-soluble methylmercury possesses the powerful ability to enter and accumulate in the human body along with the food chain, which has induced serious threats to environmental safety and human health, such as irreversible brain damage, various cognitive and motor disorders, Minamata disease, etc . Thus, establishing a sensitive detection technology for methylmercury is important and essential …”

“…2 Lipid-soluble methylmercury possesses the powerful ability to enter and accumulate in the human body along with the food chain, which has induced serious threats to environmental safety and human health, such as irreversible brain damage, various cognitive and motor disorders, Minamata disease, etc. 3 Thus, establishing a sensitive detection technology for methylmercury is important and essential. 4 The current traditional methods for methylmercury detection include inductively coupled plasma mass spectrometry, 5 gas chromatography, high-performance liquid chromatography, etc.…”