UV filter benzophenone-2: Effects on zebrafish (Danio rerio) cytochrome P450.

Benzophenone-2 (2,2', 4,4'- Tetrahydroxybenzophenone; BP-2) is widely used as a sunscreen in Personal and Care Products (PCPs) for protection against ultraviolet (UV) radiation. The effects of BP-2 on random-sex adult zebrafish (Danio rerio) cytochrome P450 (CYP450) were studied. The main goal was to investigate the detoxification mechanisms underlying the adverse consequences of exposure to xenobiotic chemicals such as BP-2. Total protein content, CYP450 content, and erythromycin N-demethylase (ERND) activity were evaluated as indicators of protein CYP3A expression. Five sets of pooled random-sex adult zebrafish were exposed to 0.0, 0.1, 5.0, and 10.0 mg/L of BP-2 to evaluate their acute and chronic toxicity (4 and 15 days, respectively). ERND activity was significantly increased in the chronic toxicity group compared to that in the control group, whereas CYP450 remained unchanged. The results suggest a sufficiently fast catalytic process that does not alter the total CYP450 content. It implies a mediation of CYP450 3A induction by BP-2 and the pregnane X receptor ligand-binding domain (PXR LBD) interaction. Ligand-protein interactions were confirmed via in silico docking with AutoDock Vina. Further computational studies indicate BP-2 potential binding affinity for the Estrogen receptor alpha ligand binding domain (ERα LBD). These results suggest that CYPs effects may result in significant toxicity in the zebrafish. Our study highlights the importance of studying biomarkers in aquatic organisms to assess xenobiotic exposure and the potential toxicity of UV filters to humans.

Toxicity of UV Filter Benzophenone-3 in Brine Shrimp Nauplii (Artemia salina) and Zebrafish (Danio rerio) Embryos.

The benzophenone (BP) family, including oxybenzone (BP-3), a prevalent sunscreen ingredient and environmental contaminant, has raised concerns since the year 2005. This study investigated oxybenzone toxicity in zebrafish (Danio rerio) eleutheroembryos and brine shrimp (Artemia salina) nauplii, focusing on the LC50 and developmental impacts. Zebrafish embryos (0.100-1.50 mg/L BP-3, 96 h) and A. salina (0.100-5.00 mg/L BP-3, 48 h) were tested with ultrasound-assisted emulsified liquid-phase microextraction (UA-ELPME) used for zebrafish tissue analysis. HPLC-DAD determined BP-3 concentrations (highest: 0.74 ± 0.13 mg/L). Although no significant zebrafish embryo mortality or hatching changes occurred, developmental effects were evident. Lethal concentrations were determined (A. salina LC50 at 24 h = 3.19 ± 2.02 mg/L; D. rerio embryos LC50 at 24 h = 4.19 ± 3.60 mg/L), with malformations indicating potential teratogenic effects. A. salina displayed intestinal tract alterations and D. rerio embryos exhibited pericardial edema and spinal deformities. These findings highlight oxybenzone's environmental risks, posing threats to species and ecosystem health.

Ecotoxicological Effects of TiO2 P25 Nanoparticles Aqueous Suspensions on Zebrafish (Danio rerio) Eleutheroembryos.

Among nanoparticles (NPs), titanium dioxide is one of the most highly manufactured worldwide and widely used in multiple products for both industrial use and personal care products. This increases the probability of release into aquatic environments, potentially affecting these ecosystems. The present study aimed to evaluate TiO2 P25 NP toxicity in zebrafish embryos and eleutheroembryos by evaluating LC50, hatching rate, embryo development, and chemical analysis of the TiO2 concentration accumulated in eleutheroembryo tissues. Zebrafish embryos ~2 h post-fertilization (hpf) were exposed to 75, 100, 150, 200, and 250 mg/L TiO2 P25 NPs for 48 and 96 h. A total of 40-60 embryos were placed in each Petri dish for the respective treatments. Three replicates were used for each treatment group. Ti4+ concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), and a conversion factor was used to calculate the TiO2 concentrations in the tissues. The highest calculated concentrations of TiO2 in zebrafish larvae were 1.0199 mg/L after 48 h and 1.2679 mg/L after 96 h of exposure. The toxicological results indicated that these NPs did not have a significant effect on the mortality and hatching of zebrafish embryos but did have an effect on their development. LC20 and LC30 were determined experimentally, and LC50 and LC80 were estimated using four different methods. Up to 11% of embryos also presented physical malformations. These effects can be detrimental to a species and affect ecosystems. Physical malformations were observed in all treatments, indicating teratogenic effects.

Synthesis, Characterization, and Ecotoxicology Assessment of Zinc Oxide Nanoparticles by In Vivo Models.

The widespread use of zinc oxide nanoparticles (ZnO NPs) in multiple applications has increased the importance of safety considerations. ZnO NPs were synthesized, characterized, and evaluated for toxicity in Artemia salina and zebrafish (Danio rerio). NPs were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and ultraviolet-visible (UV-Vis) spectroscopy. The hydrodynamic size and stability of the ZnO NP surface were examined using a Zetasizer. Characterization techniques confirmed the ZnO wurtzite structure with a particle size of 32.2 ± 5.2 nm. Synthesized ZnO NPs were evaluated for acute toxicity in Artemia salina using the Probit and Reed and Muench methods to assess for lethal concentration at 50% (LC50). The LC50 was 86.95 ± 0.21 µg/mL in Artemia salina. Physical malformations were observed after 96 h at 50 µg/mL of exposure. The total protein and cytochrome P450 contents were determined. Further analysis was performed to assess the bioaccumulation capacity of zebrafish (Danio rerio) using ICP-OES. ZnO NP content in adult zebrafish was greater in the gastrointestinal tract than in the other tissues under study. The present analysis of ZnO NPs supports the use of Artemia salina and adult zebrafish as relevant models for assessing toxicity and bioaccumulation while considering absorption quantities.

Variability of physical activity in 4 to 10-year-old children: a study by accelerometry.

INTRODUCTION: When compared to popular questionnaires, accelerometry provides more reliable information regarding physical activity. Thus, the objective has been to document the variability of physical activity in Chilean children in relation to age, gender, nutritional status and days of the week, and to determine how many of them meet the recommendation for moderate to vigorous physical activity for more than an hour a day. POPULATION AND METHODS: One hundred and nine (109) school children aged 4-10 (67 boys, 42 girls) wore an accelerometer for 2, 3 or 4 consecutive days. Of them, 30 were obese (BMI>95th percentile by age and gender). In each subject, levels of physical activity were expressed in counts per minute (cpm) and means (SD) of cpm/hour. Moderate to vigorous physical activity was defined by the daily sum of cpm>900. RESULTS: Daytime physical activity had a mean of 21,697 (662) cpm/hour with considerable variation from one child to another, and from one time of the day to another in the same child. Individual cpm/hour was significantly associated to moderate to vigorous physical activity (R = 0.954). Differences were found between girls and boys (p < 0.01) and between obese and non-obese children (p < 0.01). There were no differences between children 9 years (p = 0.12). There was a slight difference between weekdays and weekends. Fifty-six (56) of 67 boys (83.6%) and 24 of 42 girls (57.1%) met the recommendation for moderate to vigorous physical activity for more than 60 minutes a day. CONCLUSION: There is a physical activity defcit in Chilean school children under 10 years, particularly in girls and obese kids.

Variabilidad de la actividad física en niños chilenos de 4 a 10 años: estudio por acelerometría / Variability of physical activity in 4 to 10-year-old children: a study by accelerometry

Introducción. Frente a los populares cuestionarios, la acelerometría entrega una información más confiable de la actividad física. Así, el objetivo ha sido documentar la variabilidad de la actividad física de niños chilenos en relación con edad, sexo, estado nutricional y días de la semana, y determinar cuántos de ellos cumplen con la recomendación de tener actividad física moderada y vigorosa por más de una hora diaria. Población y métodos. Ciento nueve (109) escolares de 4-10 años de edad (67 niños, 42 niñas) llevaron un acelerómetro durante 2, 3 o 4 días consecutivos. Treinta eran obesos (IMC>P95 por edad y sexo). En cada sujeto, los niveles de actividad física fueron expresados en cuentas por minuto (cpm) y promedios (DE) de cpm/hora. La actividad física moderada y vigorosa se definió por la suma diaria de cpm>900. Resultados. La actividad física diurna tuvo un promedio de 21 697 (662) cmp/hora con variabilidad considerable de un niño a otro, y de un momento a otro del día en un mismo niño. Las cpm/hora individuales estaban significativamente asociadas con actividad física moderada y vigorosa (R= 0,954). Se encontraron diferencias entre niñas y niños (p <0,01) y entre obesos y no obesos (p <0,01). No hubo diferencia entre 9 años (p= 0,12). Entre semana y fin de semana hubo una leve diferencia. Cincuenta y seis de 67 (83,6%) niños y 24 de 42 (57,1%) niñas cumplieron con la recomendación de realizar actividad física moderada y vigorosa por más de 60 minutos diarios. Conclusión. Existe déficit de actividad física en escolares chilenos menores de 10 años, particularmente en niñas y en obesos.

Introduction. When compared to popular questionnaires, accelerometry provides more reliable information regarding physical activity. Thus, the objective has been to document the variability of physical activity in Chilean children in relation to age, gender, nutritional status and days of the week, and to determine how many of them meet the recommendation for moderate to vigorous physical activity for more than an hour a day. Population and methods. One hundred and nine (109) school children aged 4-10 (67 boys, 42 girls) wore an accelerometer for 2, 3 or 4 consecutive days. Of them, 30 were obese (BMI>95th percentile by age and gender). In each subject, levels of physical activity were expressed in counts per minute (cpm) and means (SD) of cpm/hour. Moderate to vigorous physical activity was defined by the daily sum of cpm>900. Results. Daytime physical activity had a mean of 21,697 (662) cpm/hour with considerable variation from one child to another, and from one time of the day to another in the same child. Individual cpm/hour was significantly associated to moderate to vigorous physical activity (R = 0.954). Differences were found between girls and boys (p < 0.01) and between obese and non-obese children (p < 0.01). There were no differences between children 9 years (p = 0.12). There was a slight difference between weekdays and weekends. Fifty-six (56) of 67 boys (83.6%) and 24 of 42 girls (57.1%) met the recommendation for moderate to vigorous physical activity for more than 60 minutes a day. Conclusion. There is a physical activity defcit in Chilean school children under 10 years, particularly in girls and obese kids.

Variabilidad de la actividad física en niños chilenos de 4 a 10 años: estudio por acelerometría / Variability of physical activity in 4 to 10-year-old children: a study by accelerometry

Introducción. Frente a los populares cuestionarios, la acelerometría entrega una información más confiable de la actividad física. Así, el objetivo ha sido documentar la variabilidad de la actividad física de niños chilenos en relación con edad, sexo, estado nutricional y días de la semana, y determinar cuántos de ellos cumplen con la recomendación de tener actividad física moderada y vigorosa por más de una hora diaria. Población y métodos. Ciento nueve (109) escolares de 4-10 años de edad (67 niños, 42 niñas) llevaron un acelerómetro durante 2, 3 o 4 días consecutivos. Treinta eran obesos (IMC>P95 por edad y sexo). En cada sujeto, los niveles de actividad física fueron expresados en cuentas por minuto (cpm) y promedios (DE) de cpm/hora. La actividad física moderada y vigorosa se definió por la suma diaria de cpm>900. Resultados. La actividad física diurna tuvo un promedio de 21 697 (662) cmp/hora con variabilidad considerable de un niño a otro, y de un momento a otro del día en un mismo niño. Las cpm/hora individuales estaban significativamente asociadas con actividad física moderada y vigorosa (R= 0,954). Se encontraron diferencias entre niñas y niños (p <0,01) y entre obesos y no obesos (p <0,01). No hubo diferencia entre 9 años (p= 0,12). Entre semana y fin de semana hubo una leve diferencia. Cincuenta y seis de 67 (83,6%) niños y 24 de 42 (57,1%) niñas cumplieron con la recomendación de realizar actividad física moderada y vigorosa por más de 60 minutos diarios. Conclusión. Existe déficit de actividad física en escolares chilenos menores de 10 años, particularmente en niñas y en obesos.(AU)

Introduction. When compared to popular questionnaires, accelerometry provides more reliable information regarding physical activity. Thus, the objective has been to document the variability of physical activity in Chilean children in relation to age, gender, nutritional status and days of the week, and to determine how many of them meet the recommendation for moderate to vigorous physical activity for more than an hour a day. Population and methods. One hundred and nine (109) school children aged 4-10 (67 boys, 42 girls) wore an accelerometer for 2, 3 or 4 consecutive days. Of them, 30 were obese (BMI>95th percentile by age and gender). In each subject, levels of physical activity were expressed in counts per minute (cpm) and means (SD) of cpm/hour. Moderate to vigorous physical activity was defined by the daily sum of cpm>900. Results. Daytime physical activity had a mean of 21,697 (662) cpm/hour with considerable variation from one child to another, and from one time of the day to another in the same child. Individual cpm/hour was significantly associated to moderate to vigorous physical activity (R = 0.954). Differences were found between girls and boys (p < 0.01) and between obese and non-obese children (p < 0.01). There were no differences between children 9 years (p = 0.12). There was a slight difference between weekdays and weekends. Fifty-six (56) of 67 boys (83.6%) and 24 of 42 girls (57.1%) met the recommendation for moderate to vigorous physical activity for more than 60 minutes a day. Conclusion. There is a physical activity defcit in Chilean school children under 10 years, particularly in girls and obese kids.(AU)