Species- and tissue-specific profiles and potential risks of polychlorinated biphenyls (PCBs) and their metabolites in dogs and cats.

In recent years, there has been growing concern about the long-term health effects of chemical exposure in pets, particularly dogs and cats, from sources such as pet food and house dust. Domestic cats (Felis silvestris catus) and dogs (Canis lupus familiaris) are continuously exposed to polychlorinated biphenyls (PCBs), with particular attention being paid to the toxicity of their metabolites, hydroxylated PCBs (OH-PCBs) and methylsulfonyl PCBs (MeSO-PCBs). However, the tissue distribution and species-specific differences of these PCB metabolites in domestic animals have not been fully elucidated.

Second phase Chiba study of mother and child health (C-MACH): Japanese birth cohort study with multiomics analyses.

Purpose: Epidemiological studies have reported that environmental factors from fetal period to early childhood can influence the risk of non-communicable diseases in adulthood. This concept has been termed the developmental origins of health and disease (DOHaD). The Chiba study of Mother and Child Health (C-MACH) is a DOHaD concept-based birth cohort study which started in 2014.

Comprehensive survey on the use of plastic additives in toy products used in Japan.

Background: Plastic additives have adverse effects on human health. Children frequently use toys that contain various substances found in paints, plasticizers, and other materials, which heighten the risk of specific chemical exposure. Infants are particularly prone to chemical exposure through the "mouthing" behavior because of the possibility of placing toys in their mouths.

The association between clustering based on composition of volatile organic compound in indoor air and building-related symptoms.

Volatile organic compounds (VOCs) have been suspected to cause building-related symptoms (BRSs). Although some studies investigated the association between BRSs and VOCs in indoor air, those results were inconsistent. This study investigated the contamination status of VOCs in the indoor air of 154 houses in Japan.

Contamination Status of Pet Cats in Thailand with Organohalogen Compounds (OHCs) and Their Hydroxylated and Methoxylated Derivatives and Estimation of Sources of Exposure to These Contaminants.

In this study, we analyzed serum samples of pet cats from Thailand and estimated the contribution to organohalogen compounds (OHCs) exposure through cat food and house dust intake. BDE-209 was predominant in cat sera and accounted for 76% of all polybrominated diphenyl ethers (PBDEs). Decabromodiphenyl ether (BDE-209) is a major contaminant in dry cat food and house dust, which has been estimated to be a source of exposure for Thai pet cats.

Determination of six thyroid hormones in dog brain and liver using acidic extraction, mixed-mode cleanup, and liquid chromatography-tandem mass spectrometry.

Thyroid hormones (THs) play a critical role in the regulation of biological processes, such as growth, metabolism, and development, in various animal species. Prohormone L-thyroxine (T4) is secreted from the thyroid gland and carried to peripheral tissues. T4 is then biotransformed to several metabolites which play different roles, mainly by iodothyronine deiodinases.

Assessment of Personal Relaxation in Indoor-Air Environments: Study in Real Full-Scale Laboratory Houses.

The relationship between chemical concentrations in indoor air and the human sense of comfort and relaxation have been reported. We investigated the effect of the sum of volatile organic compounds (ΣVOCs; sum of 79 VOCs) on the level of relaxation in two laboratory houses with almost identical interior and exterior appearances. The electroencephalogram (EEG) was monitored to evaluate the degree of personal relaxation objectively.

Association between sum of volatile organic compounds and occurrence of building-related symptoms in humans: A study in real full-scale laboratory houses.

It is well known that the indoor environment, particularly indoor air quality (IAQ), has significant effects on building-related symptoms (BRSs) in humans, such as irritation of mucosal membranes, headaches, and allergies, such as asthma and atopic dermatitis. In 2017, Chiba University launched the "Chemiless Town Project Phase 3" to investigate the relationship between IAQ and human health. Two laboratory houses (LHs) were built on a university campus in which the interiors and exteriors were similar, but the levels of indoor air volatile organic compounds (VOCs) were different.

Concentrations of Formic Acid, Acetic Acid, and Ammonia in Newly Constructed Houses.

Herein, the concentrations of formic acid, acetic acid, and ammonia in samples of indoor air for 47 new houses were measured two weeks after completion. The houses were fabricated with light-gauge steel structures. The measurements were performed in living rooms and bedrooms without furniture and outdoors.

Effects of PCB exposure on serum thyroid hormone levels in dogs and cats.

Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) might disrupt thyroid function. However, there is no clear evidence of PCB exposure disrupting thyroid hormone (TH) homeostasis in dogs and cats. The present study conducted in vivo experiments to evaluate the effects of a mixture of 12 PCB congeners (CB18, 28, 70, 77, 99, 101, 118, 138, 153, 180, 187 and 202, each congener 0.

Targeted metabolome analysis of the dog brain exposed to PCBs suggests inhibition of oxidative phosphorylation by hydroxylated PCBs.

Canis lupus familiaris (domestic dog) possess a high capacity to metabolize higher-chlorinated polychlorinated biphenyls (PCBs) to thyroid hormone (TH)-like hydroxylated PCB metabolites (OH-PCBs). As a result, the brain could be at high risk of toxicity caused by OH-PCBs. To evaluate the effect of OH-PCBs on dog brain, we analyzed OH-PCB levels in the brain and the metabolome of the frontal cortex following exposure to a mixture of PCBs (CB18, 28, 70, 77, 99, 101, 118, 138, 153, 180, 187, and 202).

Effects of 4-Hydroxy-2,3,3',4',5-Pentachlorobiphenyl (4-OH-CB107) on Liver Transcriptome in Rats: Implication in the Disruption of Circadian Rhythm and Fatty Acid Metabolism.

Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) have been detected in tissues of both wild animals and humans. Several previous studies have suggested adverse effects of OH-PCBs on the endocrine and nervous systems in mammals. However, there have been no studies on transcriptome analysis of the effects of OH-PCBs, and thus, the whole picture and mechanisms underlying the adverse effects induced by OH-PCBs are still poorly understood.

Determination of free thyroid hormones in animal serum/plasma using ultrafiltration in combination with ultra-fast liquid chromatography-tandem mass spectrometry.

Thyroid hormones (THs), which mainly consist of 3, 3', 5-triiodo-l-thyronine (T3) and L-thyroxine (T4), play a critical role in regulating biological processes such as growth and metabolism in various animal species. Thus, accurate measurement of T3 and T4, especially physiologically active free (protein-unbound) forms, in serum/plasma is needed for the evaluation of TH homeostasis. However, such high-precision determination of free THs is lacking for non-human species.

Species- and Tissue-Specific Profiles of Polybrominated Diphenyl Ethers and Their Hydroxylated and Methoxylated Derivatives in Cats and Dogs.

The adverse effects of elevated polybrominated diphenyl ether (PBDE) levels, reported in the blood of domestic dogs and cats, are considered to be of great concern. However, the tissue distribution of PBDEs and their derivatives in these animals is poorly understood. This study determined the concentrations and profiles of PBDEs, hydroxylated PBDEs (OH-PBDEs), methoxylated PBDEs (MeO-PBDEs), and 2,4,6-tribromophenol (2,4,6-tri-BPh) in the blood, livers, bile, and brains of dogs and cats in Japan.