Adverse effects of subchronic exposure to cooking oil fumes on the gonads and the GPR30-mediated signaling pathway in female rats

Spatial distributions of particle number size distributions generated during cooking processes and the impacts of range hoods

Cooking oil fume (COF) is associated with an increased risk of health effects. The particle number size distribution (PNSD) of COF presenting as lognormal structures is recognized as a key metric in determining its exposure toxicities, but the information of its spatial distributions and impacting factors are still lacking. This study conducted real-time monitoring COF PNSD during the cooking processes in a kitchen laboratory. Results showed that COF PNSD presented as a combination of two lognormal distributions. The peak diameters of PNSD inside the kitchen were: 385 nm (very close to the source), 126 nm (5 cm above the source), 85 nm (10 cm above the source) to 36 nm (breath point, 50 cm above the source), 33 nm (sucking surface of the ventilation hood), 31 nm (1 m horizontally to the source), and 29 nm (3.5 m horizontally to the source). The reasons of this observation was the sharp decrease of temperature from the pot to the indoor environment reduced the surface partial pressure of the COF particles and caused a large amount of semi-volatile organic carbons (SVOCs) with lower saturation ratios condensed on the COF surface. With the temperature difference became insignificant with the distance further to the source, the reduction of the supersaturation helped the gasification of these SVOCs. Dispersion led to a linearly horizontal decreases ((1.85 ± 0.10) × 10⁶#/cm³/m) in particle numbers with further distances, making the peak particle number concentrations decrease from 3.5 × 10⁵#/cm³ at the breath point to 1.1 × 10⁵#/cm³ at the point 3.5 m to the source. Cooking dishes also presented as mode diameters of 22-32 nm at the breath point. The amount of edible oil used in different dishes is positively correlated with the peak concentration of COF. Only increasing the exhaust force of the range hood cannot significantly change the sucked COF particle numbers and sizes, owning to that COF particles are mainly small sizes. New technologies on cleaning small size particles and efficient supplemental air should be given more considerations.

The Content and Emission form of Volatile Organic Compounds from Cooking Oils: A Gas Chromatography-Mass Spectrometry (GC-MS) Analysis

Cooking oil fumes are full of dangerous chemicals that are bad for human health. Volatile organic compounds (VOCs) in cooking oil fumes are not only emitted in the form of gas but may also accumulate with other substances in oil fumes and form particulate matter emitted into the atmosphere. Different forms of VOCs can enter different regions of the human body and have varying effects on health. This paper investigated the VOC emission types found in some cooking fumes. The findings demonstrate that organic contaminants from edible oils were released as gas and particle matter, with gas being the predominant component. The fraction of gaseous VOCs steadily declined as oil temperature rose, whereas the proportion of VOCs released as particulate matter gradually rose. It is possible to assume that the increase in oil fume with temperature was caused by the original oil's components volatilizing more frequently under the influence of vapor pressure and that chemical reactions were not the primary cause of oil fume creation.

Size-fractionated ultrafine particles and their optical properties produced from heating edible oils in a kitchen laboratory

Cooking oil fume (COF) is an important source of indoor and outdoor air pollutants. COF generates a large number of organic compounds through volatilization and thermal oxidation, mainly including acids, alcohols, aldehydes and polycyclic aromatic hydrocarbons (PAHs), which can contribute 10 %-35 % to airborne organic particles in urban areas. COF not only affects human health owning to their small sizes, but also may absorb incident light due to the presence of brown carbon (BrC) chromophores in organic components. Therefore, we investigated size distributions and light absorption properties of particles produced from heating four types of edible oil. Results showed over 75 % of COF particles belonged to ultrafine particles (UFPs) and capable of absorbing light. The particle number size distributions for heating all edible oils were bimodal lognormal distribution, and the two mode diameters were within 27.9-32.2 nm and 187.7-299.6 nm. Both real-time monitoring and offline analyzing results show the average absorption coefficients of particles generated from heating soybean oil were much greater compare to those of heating other three edible oils. The mean AAE_370/520 for heating soybean oil, olive oil, corn oil and peanut oil were 1.877, 1.669, 1.745 and 1.288, respectively, indicating the presence of BrC chromophores. A large proportion of BrC identified by HPLC-DAD-Q-TOF-MS only contain carbon, hydrogen and oxygen, which are C_nH_2nO₂, C_nH_2n-2O₂, C_nH_2n-4O₂ and C_nH_2n-6O₂ (9 <n < 23), may belong to fatty acids. Their total light absorption at λ = 370 nm accounted for 16.75 %-54.56 % of the total absorption of methanol-soluble BrC. The findings provided scientific evidences for the significance of cooking emissions on ambient aerosol properties.

In vitro and in vivo low-dose exposure of simulated cooking oil fumes to assess adverse biological effects

Cooking oil fumes (COFs) represent a major indoor environmental pollutant and exhibit potent mutagenic or carcinogenic health effects caused by containing various heterocyclic aromatic amines (HAAs) and long-chain aldehydes. Despite some evaluation of the cumulative exposure of COFs to cancer cells under high concentration were evaluated, their biological adverse effects with low-dose exposure to healthy cells had been inadequately investigated. Herein, we firstly scrutinized the three selected typically toxic compounds of heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3,8-dimethylammidazo[4,5-f]quinoxalin-2-amine (MeIQx) and trans, trans-2,4-decadienal (TDA)) emitted from COFs. In vitro studies revealed that the PhIP, MeIQx and TDA aerosol particles were negligible toxicity to cancer cells (A549 and HepG-2) but strong cytotoxicity to normal healthy cells (HelF and L02) under 0.5–4 μg/mL low dose exposure based on the reactive oxygen species (ROS) mechanism. In vivo studies demonstrated that PhIP caused significant lung and liver damage after exposure to PhIP for 30 days with mice. These results indicated the direct proof of healthy cell damage even at low-dose exposure to HAAs and aldehydes.

Emission of BTEX compounds from the frying process: Quantification, environmental effects, and probabilistic health risk assessment

Frying is one of the cooking methods which generates mono aromatic hydrocarbons, including benzene, toluene, ethylbenzene, and xylene (BTEX); subsequently, it affects health through carcinogenic (CR) and non-carcinogenic risks (n-CR). However, their environmental effects known by secondary organic aerosols (SOA) and ozone formation potential (OFP) were also attended by many scientists. Therefore, this study quantified the BTEX emissions from 4 types of most commonly used edible oils (canola, corn, sunflower, and blend) under various frying conditions of temperatures and food additives. Furthermore, the effects of the chemicals in the light of health (CR and n-CR) and environment (SOA and OFP) were also investigated. The study results showed that higher temperatures could significantly increase the emissions, while the addition of food ingredients significantly reduces the emissions. The rank order of emitted chemical was obtained as T > B > E > X. The blend had the most emission among oils, followed by, in descending order, corn, sunflower, and canola. In association with environmental effects, the orders of X > T > E > B and T ∼ E > X > B were obtained for OFP and SOA, respectively. THQ for blend, corn, canola, and sunflower oils was higher than 1 (1.76, 1.35, 1.27, and 1.002, respectively), showing a considerable n-CR when the hood was off. In this respect, TCR for the oils (1.78 × 10^-4, 1.45 × 10^-4, 1.39 × 10^-4, and 1.05 × 10^-4, respectively) shown the probable risk for all oils. Moreover, hood switching reduced the risk by about 11-81%.

Prenatal Exposure to Heavy Metals Affects Gestational Age by Altering DNA Methylation Patterns

Environmental exposure is known to have toxic effects. Maternal environmental exposure not only affects mothers but also their fetuses in utero, which may interrupt their early development. Preterm birth, one of the outcomes of prenatal exposure, is a significant factor in lifelong health risks. To understand the effects of prenatal exposome on preterm birth, we studied the association between maternal and prenatal heavy metal exposure and gestational age, using resources from the MOthers' and Children's Environmental Health (MOCEH) study in South Korea. Additionally, a methylation assay was performed to analyze epigenetic mediation using genomic DNA derived from the cord blood of 384 participants in the MOCEH study. The results suggest that maternal cadmium exposure is associated with a decrease in gestational age through an alteration in DNA methylation at a specific CpG site, cg21010642. The CpG site was annotated to a gene involved in early embryonic development. Therefore, irregular methylation patterns at this site may contribute to premature birth by mediating irregular biological mechanisms.

In vivo respiratory toxicology of cooking oil fumes: Evidence, mechanisms and prevention

BACKGROUND

As cooking is an essential part of people's daily life, cooking oil fumes (COF) has been recognized as one of the major indoor air pollutant. Mounting epidemiological evidence has indicated that COF exposure is significantly associated with an increased risk of various health effects including lung cancer, but toxicological studies are very limited.

OBJECTIVES

We conduct a systematic study to provide toxicological evidence of COF exposure on the lungs, to examine the underlying toxicological mechanism, and to suggest intervention measures to mitigate this toxicity.

METHODS

A total 96 female rats were randomly divided into control groups, COF exposure groups (0.2, 2, 20 mg/kg) and vitamin E protection groups, receiving appropriate treatment for 30 days. First we measured airway hyperresponsiveness (AHR) followed by a lung histological analysis to investigate the toxicological effects of COF. We next analyzed the biomarkers of oxidative stress, inflammation, and apoptosis to examine the underlying toxicological mechanism, and finally we investigated the protective effects of vitamin E against the toxicity of COF.

RESULTS

AHR measurement indicated that the airway resistance increased with the COF dose and the lung histological assay showed narrowing of the airway lumen, which provided evidence of the toxicological effects of COF. The biomarkers of oxidative stress (ROS and MDA), pro-inflammation (TNF-α and IL-1β), and apoptosis (NF-κB and Caspase-3) were all significantly increased with COF dose. We observed that above toxicological effects and biomarker levels induced by COF were significantly ameliorated after administration of VE.

CONCLUSION

The toxicity of cooking oil fumes on the lungs is clear from the evidence and mechanism, and can be ameliorated by vitamin E. We suggested that oxidative stress may be primarily responsible for the observed cooking oil fumes-induced toxicity.