Metal concentrations in homing pigeon lung tissue as a biomonitor of atmospheric pollution

Association of air pollutants and hospital admissions for respiratory diseases in Lanzhou, China, 2014-2019

The aim of this study was to assess the effects of air pollutants on hospital admissions for respiratory disease (RD) by using distributed lag nonlinear model (DLNM) in Lanzhou during 2014-2019. In this study, the dataset of air pollutants, meteorological, and daily hospital admissions for RD in Lanzhou, from January 1st, 2014 to December 31st, 2019, were collected from three national environmental monitoring stations, China meteorological data service center, and three large general hospitals, respectively. A time-series analysis with DLNM was used to estimate the associations between air pollutants and hospital admissions for RD including the stratified analysis of age, gender, and season. The key findings were expressed as the relative risk (RR) with a 95% confidence interval (CI) for single-day and cumulative lag effects (0-7). A total of 90, 942 RD hospitalization cases were identified during the study period. The highest association (RR, 95% CI) of hospital admissions for RD and PM_2.5 (1.030, 1.012-1.049), and PM₁₀ (1.009, 1.001-1.015), and NO₂ (1.047, 1.024-1.071) were observed at lag 07 for an increase of 10 μg/m³ in the concentrations, and CO at lag07 (1.140, 1.052-1.236) for an increase of 1 mg/m³ in the concentration. We observed that the RR estimates for gaseous pollutants (e.g., CO and NO₂) were larger than those of particulate matter (e.g., PM_2.5 and PM₁₀). The harmful effects of PM_2.5, PM₁₀, NO₂, and CO were greater in male, people aged 0-14 group and in the cold season. However, no significant association was observed for SO₂, O₃8h, and total hospital admissions for RD. Therefore, some effective intervention strategies should be taken to strengthen the treatment of the ambient air pollutants, especially gaseous pollutants (e.g., CO and NO₂), thereby, reducing the burden of respiratory diseases.

Evaluation of homing pigeon feather tissue as a biomonitor of environmental metal concentrations in China

Biomonitoring provides direct evidence of the bioavailability and accumulation of toxic elements in the environment, and homing pigeons have been proposed as a biomonitor of atmospheric pollution. We evaluated metal concentrations in homing pigeon feather tissue as a biomonitoring tool. We measured cadmium, lead, and mercury concentrations in feathers collected from 5-6-yo homing pigeons from Guangzhou, Beijing, and Harbin, China during 2011, and feathers of 1, 5, and 10-yo homing pigeons collected from Guangzhou, Beijing, and Harbin, China during 2015-16. We compared metal concentrations in feathers between sexes and among ages and evaluated spatio-temporal differences. Correlations between feather metal concentrations and previously evaluated kidney and liver metal concentrations are reported. There were no significant differences in feather metal concentrations between male and female pigeons or among 1, 5, and 10-yo pigeons. Cadmium, lead, and mercury concentrations in feathers of 1-yo pigeons were significantly correlated with concentrations in liver and kidney tissues, although the correlations were not consistent. Spatio-temporal differences in feather metal concentrations suggest the usefulness of feathers in identifying areas of concern and remedial effectiveness. Homing pigeon feather metal concentrations appear to be useful as a screening biomonitoring tool.

Changes in energetic metabolism and lysosomal destruction in the skeletal muscle and cardiac tissues of pigeons (Columba livia f. urbana) from urban areas of the northern Pomeranian region (Poland)

The aim of the present study was to evaluate the biochemical responses of the skeletal muscle and cardiac tissues of the urban pigeon as a bioindicator organism tested in diverse environments (Szpęgawa as a rural environment and Słupsk as an urban environment, Pomeranian Voivodeship, northern Poland), resulting in changes in the level of lipid peroxidation at the initial and final stages of this process and the activities of Krebs cycle enzymes (succinate dehydrogenase, pyruvate dehydrogenase, isocitrate dehydrogenase, and alfa-ketoglutarate dehydrogenase). Szpęgawa village was chosen due to the intensive use of the European motorway A1 with significant traffic and pollution levels. The concentration of Pb was higher in the soil and feathers of pigeons nesting in the polluted areas (Szpęgawa). Our studies have shown that the presence of lead in soil and feathers of the pigeons resulted in the activation of lipid peroxidation, destabilization and increased activity of lysosomal membranes, and activation of mitochondrial enzymes of the Krebs cycle with energy deficiency (reduction of ATP levels) in cardiac and skeletal muscle tissues simultaneously.

Profile of Heavy Metals and Antioxidant Defense in the Muscle Tissues of Pigeons (Columba livia f. urbana) from Anthropogenically Transformed Areas in the Pomeranian Region (Northern Poland)

Pigeons can be successfully used as bioindicators of a contaminated environment. We studied the relationship between the functioning of the pro/antioxidant balance in muscle tissues (skeletal muscle and cardiac tissues) of pigeons (Columba livia f. urbana) living in areas with different levels of pollution (Pomeranian Voivodeship, Northern Poland). The current study demonstrated the impact of the environment with preferential high Pb contamination in soil and feathers of pigeons on the formation of adaptive redox mechanisms in muscle tissues. An increase in the intensity of lipid peroxidation (estimated by the TBARS level) accompanied by enhancement of the oxidative modification of proteins (aldehydic and ketonic derivatives) and an important decrease in the activity of antioxidant enzymes (SOD, CAT, and GR) in pigeon muscle tissue was observed. These changes in enzyme activities were dependent on the type of muscle tissue (skeletal muscle and cardiac tissues). Our results confirm the concept of the recalculation of the De Ritis ratio (AsAT/AlAT) in both types of muscles indicating the tendency to cardio- and hepatocellular damage and toxicity caused by heavy metals from the polluted environment.

Non-invasive biomonitoring of organic pollutants using feather samples in feral pigeons (Columba livia domestica)

A large portion of organic pollutants (OPs) represent a potential hazard to humans and living beings due to their toxic properties. For several years, birds have been used as biomonitor species of environmental pollution. Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated biphenyl ethers (PBDEs), organophosphate pesticides (OPPs), polycyclic aromatic hydrocarbons (PAHs) and pyrethroids (PYRs) were assessed in body feather samples of 71 feral pigeons (Columba livia domestica) collected from Asturias and Galicia (NW Spain). The percentage of detection for all chemical groups were above 90% in studied birds. The general pattern was dominated by PAHs (mean value ± standard deviation (SD) 32 ± 15 ng/g) followed by OCPs (3.8 ± 1.1 ng/g), PYRs (3.4 ± 3.8 ng/g), PCBs (1.6 ± 1.0 ng/g), OPPs (1.3 ± 0.70 ng/g) and PBDEs (0.80 ± 0.30 ng/g). Significant differences were observed between age, location and gender suggesting different sources of exposure and accumulation pathways.

Ambient air pollution and daily hospital admissions for respiratory system-related diseases in a heavy polluted city in Northeast China

Respiratory disease admission has been increasing in the recent 5 years due to heavy air pollutions and bad weather conditions in China. We investigated the short-term association of ambient air pollution with daily counts of hospital admissions due to respiratory infection diseases with stratified analysis by age (0-18, 19-65, and > 65 years old), gender (male, female), season (spring, summer, autumn, winter), and disease type (lung infections, asthma, COPD (chronic obstructive disease), URI (upper respiratory infections)) in heavy polluted city of Shenyang in China. Daily ambient air pollution concentrations, weather conditions, and hospital admission counts for 53 months (from November 1, 2013 to March 25, 2018) were extracted from related authorities in electronic databases. Associations between outdoor air pollution levels and hospital admissions were estimated for time lags of 0-7 days using quasi-Poisson additive regression models, adjusted for meteorological variables, holidays, day of week, and season, as well as eliminating autocorrelations. Single pollutant analysis results showed lung infection diseases were related to all pollutant concentration change with no lag effects. After adjusting for other pollutants and confounding factors, we found NO₂ was associated with daily admissions of lung infections (ER = 6.75%, 95% CI 1.24, 12.55), asthma (ER = 20.36%, 95% CI 4.26, 38.95; lag day 5, ER = 18.48%, 95% CI 2.83, 36.51), and COPD (ER = 13.27%, 95% CI 0.46, 27.71); CO was associated with lung infections and asthma with lag effects on lag days 1 and 4; and PM_2.5 was associated with COPD admissions on lag day 6. Respiratory hospital admissions in female over 65 years old and autumn were more associated with increased air pollutant levels. Our study results might add more detail evidences for relationship studies between air pollution exposure and respiratory diseases and contribute to the precise respiratory disease prevention and air pollution control strategies.

Blood mercury levels in mute swans (Cygnus olor) are not related to sex, but are related to age, with no blood parameter implications

Concentrations of mercury (Hg) were examined in the blood of mute swans from rural breeding sites and urban wintering areas in southern parts of Poland, Europe. The birds were classified into three age groups: cygnets, juveniles and adults. To investigate the potential impact of Hg on birds, hematocrit (Ht), reduced glutathione (GSH) levels and morphometric measurements were taken. Using morphometric parameters, we stated that all mute swans sampled were in good condition. The mercury concentrations found were rather low and differed between birds from industrialized wintering areas and rural breeding areas (means 7 ng/mL and 2 ng/mL, respectively). We found no difference in Hg concentrations between the sexes, but concentrations varied significantly between age groups (cygnets 2 ng/mL, juveniles 7 ng/mL and adults 6 ng/mL). A similar trend was observed for hematocrit levels. GSH levels did not differ between any of the groups studied. We found no significant relationship between blood parameters (Ht, GSH) in relation to Hg concentrations. We conclude that the Hg concentrations in blood may be influenced by industrialization, season and age, but generally low concentration such as those found by us do not affect Ht and GSH levels.