لخّصلي

Daphnia pulex heart rate, highly sensitive to toxins, serves as a quantifiable indicator of chemical toxicity, offering a non-specific screening method for assessing systemic effects beyond aquatic ecosystems. Exposure to chemicals extracted from thermal bill paper caused a dose-dependent decrease in Daphnia heart rate, with complete cardiac arrest (0 bpm) observed at 5 mg/L after 24 hours. This cardiotoxicity, increasing with concentration and exposure time, highlights the potential human health risks, mirroring the cardiovascular effects of Bisphenol S (BPS) found in thermal paper. Analysis identified BPS and Diphenyl Sulfone (DPS) in the paper extract. In-silico analysis using SwissADME predicted high bioavailability for both, with DPS potentially crossing the blood-brain barrier. The acute toxicity of these compounds, confirmed by Daphnia tests, emphasizes the need for safer alternatives in thermal bill paper production due to potential adverse health and environmental impacts. The study utilized FTIR, HR-MS, and in-silico tools for a robust safety assessment.

326 The heart of Daphnia pulex is highly sensitive to toxicants, making changes in its heart rate a
327 direct and quantifiable indicator of stress and toxicity. Monitoring these changes is crucial in
328 understanding the broader toxicological impacts of thermal bill paper chemicals, beyond
329 specific environmental concerns. Unlike studies focused solely on aquatic ecosystems, this
330 approach offers a non-specific screening method to assess the systemic effects of chemical
331 exposure, providing insights into overall physiological distress. Moreover, since chemicals
332 like Bisphenol S (BPS), found in thermal bill paper, are known to affect cardiovascular health
333 in humans, studying their impact on Daphnia pulex can offer predictive value for potential human health risks. The use of Daphnia pulex allows for rapid, ethical testing, yielding
335 immediate data on cardiotoxicity that can guide further toxicological evaluations and inform
336 public health recommendations The results from the study show a clear dose-dependent decrease in the heart rate of
339 Daphnia pulex when exposed to increasing concentrations of the chemical extracted from
340 thermal bill paper over various time intervals. The cardiac event data for Daphnia pulex at
341 various concentrations and time intervals are presented in Table 4. At the 2-hour mark, the
342 heart rates of the Daphnia were relatively stable across all concentrations, with the control
343 group showing a rate of 478 beats per minute (bpm) and the highest concentration (5 mg/L)
344 showing a significant reduction to 242 bpm. As time progressed, the heart rates in all groups
345 exposed to the chemical steadily declined. By the 24-hour mark, a more pronounced reduction in heart rate was observed,
351 particularly in the groups exposed to higher concentrations. The heart rate in the 5 mg/L
352 group dropped to 0 bpm, indicating complete cardiac arrest, while the control group
353 maintained a heart rate of 390 bpm. The pattern continued at the 48-hour and 72-hour
354 intervals, where the higher concentrations (1 mg/L, 2 mg/L, and 5 mg/L) showed dramatic
355 decreases in heart rate, with the 5 mg/L group showing no heartbeats after 24 hours. In
356 contrast, the control group experienced a gradual decline but maintained a heartbeat throughout the 72-hour period, ending at 290 bpm. These findings suggest that the chemical
358 extracted from thermal bill paper has a significant cardiotoxic effect on Daphnia pulex, with
359 the severity of the effect increasing both with higher concentrations and longer exposure
360 times.
361 4. Conclusion
362 The study provided a comprehensive analysis of the chemical composition of thermal bill
363 paper, revealing the presence of potentially hazardous compounds such as Bisphenol S (BPS)
364 and Diphenyl Sulfone (DPS). The extraction process using ethyl acetate as the solvent was
365 effective, as evidenced by the TLC results showing distinct spots corresponding to the
366 compounds of interest. The subsequent FTIR and HR-MS analyses confirmed the presence of
367 these compounds by identifying characteristic functional groups and matching molecular
368 weights with known standards. The identification of BPS and DPS as major constituents
369 aligns with their known usage in thermal paper due to their functional properties.
370 The in-silico analysis using the SwissADME web tool provided significant insights
371 into the pharmacokinetic properties of BPS and DPS. The bioavailability radar plots indicated
372 that both compounds possess properties within the optimal range for absorption and
373 bioavailability, except for their low degree of saturation, which could affect their clinical
374 efficacy. The BOILED-Egg model predicted that BPS is likely to be absorbed by the
375 gastrointestinal tract, while DPS could potentially cross the blood-brain barrier, raising
376 concerns about its impact on the central nervous system. The lack of P-glycoprotein
377 recognition further implies that these compounds might persist in the CNS, potentially
378 leading to adverse neurological effects. The toxicity studies conducted using Daphnia pulex
379 provided additional evidence of the potential harm posed by these chemicals. The acute
380 toxicity tests demonstrated that at higher concentrations, both BPS and DPS exhibit significant toxicity, further supporting the notion that their presence in thermal bill paper
382 could pose a serious risk to human health and the environment. These findings are consistent
383 with existing literature, which has raised concerns about the widespread use of bisphenol
384 compounds in consumer products and their potential endocrine-disrupting effects.
385 In conclusion, the study highlights the need for increased scrutiny and regulation of
386 the chemicals used in thermal bill paper. The presence of BPS and DPS, coupled with their
387 potential to persist in human tissues and cause adverse health effects, underscores the
388 importance of finding safer alternatives. The use of advanced analytical techniques such as
389 FTIR and HR-MS, combined with in-silico tools like SwissADME, provides a robust
390 framework for assessing the safety of chemical compounds in consumer products. As the
391 understanding of the health risks associated with bisphenol compounds continues to evolve, it
392 is crucial to explore and adopt safer alternatives to protect public health and the environment.
393 Acknowledgements
394 We are thanking Indian Institute of Science for providing the library and instrumentation
395 facilities.
396 Declarations
397 Ethical Approval
398 “not applicable”.
399 Competing interests
400 The authors declare that they have no conflict of interest.
401 Funding
402 No funding support.
403 Availability of data and materials
404 The data and materials are attached as supporting information.