مجله طب دریا
سال چهارم شماره 3 (پیاپی 16، پاییز 1401)

Lead is a toxic metal that is highly distributed in the environment and enters the natural cycle through many human-made industrial, agricultural, urban and rural activities, as well as by entering the marine ecosystems, it accumulates in the cycle of food and fish and can cause very dangerous and carcinogenic diseases in humans. This review was conducted in 2022. The data needed to assess the risk of lead on fish in the Caspian Sea, Oman sea and the Persian Gulf were collected by reviewing Persian and English published articles. The findings showed that the range of lead concentration in Caspian Sea fish was from 0.03 mg/kg in Vimba vimba to 3.01 mg/kg in golden grey mullet. Among the fish of the Persian Gulf and the Oman Sea, the highest amount of lead was found in the flounders (2.82 mg/kg) and the lowest amount of this metal was found in sulpdur goatfish (0.008 mg/kg). The amount of lead in the muscle of the fish studied in the Caspian Sea, such as Caspian kutum, Golden grey mullet, common carp, leaping mullet, Gobies, and common Pike, was higher than the permissible limit of the World Health Organization (WHO) standard (0.2 mg/kg). In fish in the Persian Gulf and the Oman Sea, the levels of lead in the muscles of Narrow-barred Spanish mackerel, Tigertooth croaker, Indo-Pacific king mackerel, Chelon subviridis, blackspotted croaker, Cobia, Sillaginidae, and Flounder were reported to be higher than the WHO limit. According to the risk assessment of lead metal in the fishes, in many cases the risk index was higher than 1 and the carcinogenic risk index of lead in the muscle of many fishes was reported to be higher than 1×10-4. Therefore, according to these results, it can be concluded that many fish in the Caspian Sea, the Persian Gulf, and the Oman Sea have been contaminated with lead metal during the past years, and for human consumption, the necessary precautions should be taken based on the recommendations of the WHO. It is also suggested to continuously monitor and control the concentration of lead metal and other heavy metals in marine ecosystems.

Heavy metals are one of the most common environmental pollutants that can enter coastal areas from natural and human sources and affect marine organisms and the human population. Heavy metals are a serious threat to human health, living organisms and natural ecosystems due to their toxicity, persistence and bioaccumulation characteristics. Many heavy metal ions are toxic or carcinogenic to humans. Heavy metals can lead to the destruction of marine ecosystems by reducing the diversity and number of species and through accumulation in living organisms and food chains. Heavy metals enter coastal and marine environments through various sources, including industries, and domestic sewage. Heavy metals from ship traffic effluents are among polluting sources. This study investigated the effect of this pollution on macrobenthic communities. The findings show that heavy metals have an effect on premature spawning, increase in mortality and decrease in the body's defense system in fish, decrease in growth and survival and irregular cell division in sea urchins, increase in mortality, delay in growth and prevention shell development and irregular cell division in crustaceans, and increased mortality, reducing body defenses, delaying growth, losing breeding capacity and reducing eggshell thickness in seabirds, and irregular structure and acute toxic condition and delay in growth in benthos. Urban and industrial activities are the main sources of marine environment pollution. As a result, it can be stated that environmental quality assessment in this sector can provide useful information for pollution control in coastal areas. Recently, the implementation of environmental legal frameworks in the European Community has increased the awareness of the importance of heavy metals in shipping effluents in order to achieve "good environmental status".

Given the importance of marital satisfaction in all aspects of quality of life; the aim of this study was to predict marital satisfaction through job stress in sailors.

The present research was a descriptive-correlational study conducted in Bushehr city, south of Iran in 2022. The statistical population was married sailors aged 35 to 40 years in Bushehr city, who were included in the study by available sampling. The sample size was 60 sailors who volunteered to participate in the study. Osipow's (1987) occupational stress and Enrich's (1998) marital satisfaction questionnaires were used to collect data.

There is a significant negative relationship between job stress and marital satisfaction (p=0.001). The results of regression analysis showed that job stress explains 43% of the variance of marital satisfaction.

Considering the existence of job stress in maritime work and the importance of 43% job stress in predicting marital satisfaction, it is suggested to develop strategies to reduce job stress in sailors so that sailors are protected from short-term and long-term complications of lack of marital satisfaction.

One of the most important ways of spending leisure time is using swimming pools and water parks. Therefore, the current research, in order to maintain the physical and mental health of the users of these places, seeks to develop a model for water safety in swimming pools by using appropriate strategies.

The current qualitative research was conducted using the foundation data model. The statistical population was university faculty members in the department of sports management and medical sciences, officials of the sports and youth department, experts in the field of construction and equipping of sports facilities, managers and users of swimming pools in Mazandaran province, north of Iran in 2022. The non-random sampling method; and a semi-structured interview with open questions were used. The interviews continued until theoretical saturation (Interview No. 18). In order to finalize the research, validity and reliability criteria were used.

After removing the similar codes, 64 concepts were identified in the field of water safety development in swimming pools, which are in two main categories of operational development (including technical measures, security measures, emergency services, health measures) and strategic development (including training and culture, preventive measures).

Some important recommendations in the field of developing a model for water safety in swimming pools include preventing the formation of calcareous deposits on the surface of the pool, preventing the growth of algae in the pool, having an oxygen device in swimming pools and familiarizing rescuers and lifeguards with resuscitation methods and quick connection with medical centers.

Food poisoning is the most common and important form of the food-borne disease caused by consuming contaminated food. The present study was conducted with the aim of determining the knowledge, attitude and practice of students of Chabahar University of Maritime and Marine Sciences in the field of food poisoning.

The current study was a cross-sectional descriptive study that was conducted in 2022. The research population was all students studying at Chabahar University of Maritime and Marine Sciences. The sample size of 150 people was calculated. The tool of data collection was the questionnaire of knowledge, attitude and practice of students in the field of food poisoning, whose reliability and validity were confirmed.

The mean and standard deviation of students' knowledge, attitude and performance scores were 20.33±3.09, 43.14±5.11 and 13.04±5.64, respectively. The mean knowledge score in 61% of students was estimated at a good level. The mean attitude score in 64% of students was at the moderate level, and practice was reported to be poor in 58%. A statistically significant relationship was observed between knowledge and level of education and practice with a history of poisoning in students (P<0.05).

Despite the high level of knowledge and a moderate level of attitude in students, their practice was at a poor level. Considering the sensitive job of naval students in the future who spend a long time on the ship, it is suggested to hold training workshops with the aim of improving their practice in the field of food poisoning.

Zinc is one of the heavy metals in aquatic ecosystems. Currently, nanotechnology has made significant progress in various industries, in the present study, the toxicity of nano-zinc oxide on the blood indices of Capoeta capoeta gracilis (Capoeta) was investigated.

This research was conducted with concentrations of 0, 5, 20, 100 and 400 mg/L of nano-zinc oxide (Nano-ZnO) for 14 days on 70 Capoeta with a mean weight of 20±5 grams. After the experiment, blood samples were taken from the Capoeta and various blood indices were measured including leukocytes, lymphocytes, neutrophils, eosinophils, erythrocytes, hemoglobin, hematocrit, MCV, MCH and MCHC.  

All blood erythrocyte indices in Capoeta showed significant changes, but leukocyte indices did not change. Also, with the increase of nano-zinc oxide in different treatments, the number of red blood cells, hemoglobin and hematocrit decreased and the number of white blood cells increased in Capoeta.  

With rising the concentration of nano-zinc oxide, the level of hematological adverse effects increased and the concentration of 100 mg/l has the most adverse effects in Capoeta. Nano-zinc oxide causes anemia and disrupts Capoeta's immune system, which may be due to its destructive effects on hematopoietic organs such as the liver and kidney.

The present research was carried out with the aim of measuring the levels of the heavy metals nickel, lead and cadmium in the muscle tissues of the Acanthopagrus cuvieris in Asaluyeh port in Bushehr Province.

Twenty Acanthopagrus cuvieri with an average weight of 1056.66±10.12 and 1014.30±19.68 gr were hunted in the winter and spring of 2020, respectively. After transferring the samples to the laboratory, their Biometrics operations were performed. Then the samples were chemically digested with nitric acid and at the end, the number of heavy metals was measured with an atomic absorption spectrophotometer (model: PG AA 500).

The results of measuring the concentrations of the heavy metals in the muscle tissues of the Acanthopagrus cuvieri showed that the mean levels of nickel, lead and cadmium were 36.4±0.2, 85.4±0.4 and 58.7±0.1 µg/kg dry weight during winter, respectively. In spring, these amounts were 12.8±0.4, 45.3±0.5 and 48.2±0.3 µg/kg dry weight, respectively. There was a significant difference between winter and spring in this regard (P<0.05).

The levels of heavy metals in muscle tissues of Acanthopagrus Cuvieri in Asaluyeh port were lower than the international WHO, FAO, NHMRC, and UK (MAFF) standards and therefore these concentrations pose no threat to consumers.