scholarly journals Development of cancerogenic risk index maps for the territory of Vladikavkaz

2021 ◽  
Author(s):  
В.Б. Заалишвили ◽  
О.Г. Бурдзиева ◽  
А.С. Кануков ◽  
Л.В. Дзобелова
Keyword(s):  
Public Health ◽  
Environmental Pollution ◽  
Risk Index ◽  
Age Groups ◽  
Mining Industry ◽  
Carcinogenic Risk ◽  
Malignant Neoplasms ◽  
Interpolation Methods ◽  
Cancer Morbidity ◽  
High Level

В последние годы наблюдается значительный рост численности населения, которому соответствуют ускоренные темпы индустриализации. Это сопровождается всё более значительным загрязнением окружающей среды тяжелыми металлами. Наибольший вклад в загрязнение окружающей среды Республики Северная Осетия – Алания долгие годы вносила горнодобывающая промышленность, в последнее же время к ней, в качестве не менее весомого источника загрязнения присоединились нестационарные источники. Загрязнение тяжелыми металлами создает серьезную опасность для здоровья населения и окружающей среды из-за их токсичной природы. Цель исследования. Разработка карт пространственного распределения загрязняющих веществ является основой в оценке уровня загрязнения окружающей среды. Цель настоящего исследования – разработка карт индекса канцерогенного риска и установление его взаимосвязи с онкозаболеваемостью населения. Методы исследования. В процессах создания карт используются методы интерполяции, так как количество проб и измерений содержания вредных веществ в той или иной среде, как правило, весьма ограничено. Согласно зарубежным исследованиям, для большинства наиболее часто используемых методов интерполяции обеспечивается одинаково высокая точность. В настоящей работе при расчёте индексов канцерогенного риска использовался метод обратного взвешивания расстояний. Результаты работы Отобран материал по заболеваемости населения злокачественными образованиями по различным районам г. Владикавказа. Основной удельный вес вновь зарегистрированных злокачественных новообразований приходится на возрастные группы свыше 60 лет. Анализ онкозаболеваемости показал, что в тех районах г. Владикавказа, где уровень загрязнения окружающей среды выше, выше и показатели онкозаболеваемости. Проведен расчёт индекса риска для здоровья населения при воздействии химических веществ загрязняющих окружающую среду. По всем исследуемым показателям наблюдается значительное превышение предельно допустимых значений, за исключением ртути. Полученные данные о высоком уровне канцерогенного риска согласуются с высоким уровнем онкологической заболеваемости на территории города, что говорит о тесной взаимосвязи заболеваемости и индекса канцерогенного риска. In recent years, there has been a significant increase in the population, which is matched by the accelerated rate of industrialization. This is accompanied by increasingly significant pollution of the environment with heavy metals. For many years, the mining industry has made the greatest contribution to the environmental pollution of the Republic of North Ossetia – Alania, non-stationary sources have recently joined as an equally significant source of pollution. Heavy metal pollution poses a serious threat to public health and the environment due to its toxic nature. Aim. The development of maps of the spatial distribution of pollutants is the basis for assessing the level of environmental pollution. The aim of this study is to develop maps of the carcinogenic risk index and to establish its relationship with the incidence of cancer in the population. Methods. In the process of creating maps, interpolation methods are used, since the number of samples and measurements of the content of harmful substances in a particular environment is usually very limited. According to foreign studies, for most of the commonly used interpolation methods, equally high accuracy is provided. In the present work, we used the method of the inverse weighting of distances for calculating the indices of carcinogenic risk. Results. The material on the incidence of malignant neoplasms in the population in various districts of Vladikavkaz was selected. The main share of newly registered malignant neoplasms falls on the age groups over 60 years old. The analysis of cancer morbidity showed that in those areas of Vladikavkaz where the level of environmental pollution is higher, the indicators of cancer morbidity are also higher. The calculation of the risk index for public health under the influence of chemical substances polluting the environment has been carried out. For all the studied indicators, there is a significant excess of the maximum permissible values, with the exception of mercury. The obtained data on the high level of carcinogenic risk is consistent with the high level of cancer incidence in the city; it indicates a close relationship between the incidence and the carcinogenic risk index.

scholarly journals Isolasi dan Identifikasi Bakteri Resisten Arsen pada Sedimen di Pesisir Laut Buyat Tahun 2018

2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Natalia M. Pantow ◽  
Billy J. Kepel ◽  
. Fatimawali
Keyword(s):  
Environmental Pollution ◽  
Coastal Area ◽  
Human Life ◽  
Mining Industry ◽  
Toxic Metal ◽  
Resistant Bacteria ◽  
North Sulawesi ◽  
Soil Sediment ◽  
High Level ◽  
Arsenic Resistant Bacteria

Abstract: Metals are very important and widely used in many aspects of human life, however, they can cause environmental pollution which is harmful to life. Arsenic is a very toxic metal that can cause kidney damage and is responsible to various chronic health problems, especially cancer. The coastal area of Buyat Sea in North Sulawesi Province has a high level of activity in mining industry. The mining waste results in environmental pollution due to arsenic release, thus triggers the occurence of arsenic-resistant bacteria. This study was aimed to determine whether there were arsenic-resistant bacteria in soil sediment originated from the coastal area of Buyat Sea and to identify the types of arsenic-resistant bacteria. This was a descriptive explorative study. Samples of soil sediment were obtained from one point on the coastal area of Buyat Sea. The results showed that there were 10 isolates of arsenic-resistant bacteria. There were five genera of bacteria that were resistant to arsenic, namely Escherichia, Klebsiella, Hafnia, Staphylococcus, and Bacillus. Conclusion: In the coastal area of Buyat Sea, five genera of arsenic-resistant bacteria were identified, as follows: Escherichia, Klebsiella, Hafnia, Staphylococcus, and Bacillus.Keywords: arsenic, sediment, arsenic-resistant bacteria Abstrak: Logam sangat penting dalam berbagai aspek kehidupan manusia walaupun dapat mencemari lingkungan dan berbahaya bagi kehidupan. Arsen merupakan logam berat yang sangat bersifat toksik dan dapat merusak ginjal serta bertanggung jawab terhadap berbagai gangguan kesehatan kronis, termasuk kanker. Daerah pesisir Buyat laut di Provinsi Sulawesi Utara memiliki tingkat aktivitas yang tinggi dalam bidang industri pertambangan. Limbah pertambangan mengakibatkan terjadinya pencemaran lingkungan oleh karena pelepasan arsen yang dapat memicu terjadinya bakteri resisten arsen. Penelitian ini bertujuan untuk mengetahui apakah terdapat bakteri resisten arsen pada sedimen yang berasal dari daerah pesisir laut Buyat dan untuk mengidentifikasi jenis bakteri resisten arsen yang ditemukan. Jenis penelitian ialah deskriptif eksploratif. Sampel penelitian ialah sedimen tanah di satu titik di pesisir laut Buyat. Hasil penelitian mendapatkan 9 isolat bakteri resisten arsen dan ditemukan lima genus bakteri yang resisten terhadap arsen yaitu Escherichia, Klebsiella, Hafnia, Staphylococcus, dan Bacillus. Simpulan: Di daerah pesisir laut Buyat ditemukan bakteri resisten arsen pada sedimen yaitu genus Escherichia, Klebsiella, Hafnia, Staphylococcus, dan Bacillus.Kata kunci: arsen, sedimen tanah, bakteri

scholarly journals Assessment of carcinogenic risk from exposure to chlororganic compounds of water of systems of centralized water supply

2021 ◽  
Vol 100 (2) ◽  
pp. 99-110
Author(s):  
Boris I. Marchenko ◽  
Petr V. Zhuravlev ◽  
Nina K. Plugotarenko ◽  
Aleksandra I. Yuhno
Keyword(s):  
Drinking Water ◽  
Water Supply ◽  
Natural Water ◽  
High Efficiency ◽  
Tap Water ◽  
Carcinogenic Risk ◽  
Organochlorine Compounds ◽  
Malignant Neoplasms ◽  
Water Supply Systems ◽  
High Level

Introduction. The problem of providing the population with drinking water with guaranteed quality, safety, and physiological usefulness is highly relevant for many regions of Russia. The use of chlorination for disinfection of the water is a potential cause of the formation of excess concentrations of organochlorine compounds in it, including trihalogenomethanes, which leads to elevated levels of carcinogenic risk. The study’s object was: data on the content in water of centralized water supply systems of carcinogenic organochlorine compounds - chloroform, dichlorobromomethane and chlorodibromomethane. Material and methods. information on the incidence of the population of malignant neoplasms; the results of an experiment to evaluate the effectiveness of the preliminary ammonization method. The paper used methods of health risk assessment, variation statistics, and mathematical modeling. Results. The use of preliminary ammonization in Taganrog prevents the formation of trihalogenomethanes and ensures the maintenance of an individual multi-route carcinogenic risk at an acceptable level (9.933 · 10-6). Systematic unreasonable hyper chlorination of river water without prior ammoniation is the main reason for the excess content of chlororganic compounds and the high level of individual carcinogenic risk in the Primorsky rural settlement of the Neklinovsky District - up to 3.234 · 10-3 in 2015. Modeling on the basis of experimental chlorination of natural water indicates the high efficiency of preliminary ammonization in the disinfection mode, which ensures the content of free total active chlorine in tap water in the range from 0.8 to 1.2 mg/l. Conclusion. The high efficiency of the application of preliminary ammonization of natural water to prevent the formation of trihalogenomethanes and reduce carcinogenic risk has been confirmed. The priority factor for the formation of excess amounts of organochlorine compounds in drinking water is its hyper chlorination. Promising measures to reduce the carcinogenic risk of trihalogenomethanes in tap water include the systematic monitoring of their content, the use of preliminary ammonization, the exact dosage of chlorine, the deep purification of the source water before chlorination, the replacement of primary chlorination with ultraviolet disinfection, and others.

scholarly journals ECOLOGOEPIDEMIOLOGICAL CONNECTION OF LUNG CANCER MORBIDITY WITH ATMOSPHERIC AIR POLLUTION BY CARCINOGENS IN PETROCHEMICAL PROFILE REGIONS

2018 ◽  
Vol 35 (3) ◽  
pp. 45-57 ◽  
Author(s):  
G G Maksimov ◽  
Yu G Aznabaeva ◽  
E V Kirillova ◽  
O N Lipatov ◽  
V M Akhmetov
Keyword(s):  
Lung Cancer ◽  
Structural Data ◽  
Carcinogenic Risk ◽  
Malignant Neoplasms ◽  
Industrial Emissions ◽  
Atmospheric Air ◽  
Industrial Enterprises ◽  
Republic Of Bashkortostan ◽  
Cancer Morbidity ◽  
The Republic

Aim. To study the dynamics of lung cancer (LC) morbidity among the population of five cities of the Republic of Bashkortostan over the period from 2010 to 2016 and the structure of industrial emissions for grounding of adequate integral index, connected with LC morbidity and development of preventive measures to decrease malignant neoplasms. Materials and methods. The structure of gross emissions of industrial enterprises and ecologohygienic assessment of atmospheric air was conducted according to the materials of the Department of Rospotrebnadzor in Bashkortostan for 2010-2016. Lung cancer morbidity in the above mentioned territories was studied by the materials of Republican Clinical Oncological Dispensary. To estimate the influence of gross emissions on LC morbidity, modeling technique, adequate to panel analysis of spatially dynamic structural data, was applied. Results. The assessment of carcinogenic risk of atmospheric air emissions, taking into account not separate carcinogens, but their combined effect as substances with similarly directed impact, detected accurate correlation of dependence of high LC morbidity on the resultant carcinogens action. Conclusions. High LC morbidity in the cities of Bashkortostan is connected with high gross emission of carcinogens into the atmospheric air. Information on gross emissions of carcinogens and their structure can serve as an integral criterion of atmospheric pollution impact on lung cancer morbidity.

HYGIENIC IMPACT ASSESSMENT OF EMISSIONS OF PETROCHEMICAL PLANTS AND PETROLEUM REFINERIES ON CANCER MORBIDITY IN A LARGE INDUSTRIAL CENTER

2020 ◽  
pp. 84-95
Author(s):  
Z.B. Baktybaeva ◽  
R.A. Suleymanov ◽  
T.K. Valeev ◽  
E.G. Stepanov ◽  
N.Kh. Davletnurov ◽  
...  
Keyword(s):  
Public Health ◽  
Air Pollution ◽  
Mortality Rate ◽  
Impact Assessment ◽  
Cancer Mortality ◽  
Pearson Correlation ◽  
Malignant Neoplasms ◽  
Primary Cancer ◽  
Cancer Morbidity ◽  
Petroleum Refineries

Introduction. Petrochemical and refinery enterprises generate up to 80 % of emissions from all stationary sources in Ufa. Air toxic pollution can threaten public health. The purpose of the study is to conduct hygienic impact assessment of emissions from petrochemical and refinery enterprises on cancer morbidity in Ufa. Materials and Methods. The authors examined the data on air carcinogen concentrations and indicators of general mortality, primary cancer morbidity, patient cohorts with malignant neoplasms and cancer mortality rate in Ufa between 2007 and 2017. They also calculated Pearson correlation coefficients and carcinogenic risks. Results. At some instants, benzene, gasoline, ethylbenzene and ethenylbenzene concentrations exceeded the maximum permissible concentration 5 times or more; concentrations of formaldehyde, benzo(a)pyrene and carbon (soot) were 2 times higher than the norm. In 2007–2017, the rate of newly diagnosed cancer morbidity increased by 6.0 %, the number of cancer patients – by 6.9 %. Over the last 4 years, cancer mortality rate reached its maximum during the given period, namely 200.1 per 100 000 people (mean value between 2007 and 2017 was 165.6±15.6). The authors revealed a close correlation between the patient cohort with malignant neoplasms and carbon (r=0.74) or ethylbenzene (r=0.63) emissions. The trichloromethane concentration was closely correlated with indicators of primary cancer morbidity (r=0.82) and mortality (r=0.78). The rate of carcinogenic risks due to air pollution was 9.0×10-4, i.e. unacceptably high. The rate of population aerogenic carcinogenic risks resulted in 1000 additional cases of malignant neoplasms. Conclusion. If there are no changes in the existing levels of air pollution in Ufa, further environmental aggravation associated with carcinogenic risks and reduction in life expectancy among Ufa residents can be possible. Keywords: air pollution, carcinogens, cancer morbidity and mortality, public health risks. В Уфе предприятия нефтехимии и нефтепереработки формируют до 80 % выбросов от всех стационарных источников. Загрязнение воздушного бассейна токсичными веществами может представлять опасность для здоровья населения мегаполиса. Цель исследования. Гигиеническая оценка влияния выбросов предприятий нефтехимии и нефтепереработки на онкологическую заболеваемость населения г. Уфы. Материалы и методы. Проанализированы данные о содержании в атмосферном воздухе г. Уфы химических веществ, обладающих канцерогенным действием, а также показатели общей смертности населения, первичной онкологической заболеваемости, контингента больных злокачественными новообразованиями и смертности от онкологических заболеваний за 2007–2017 гг. Рассчитаны коэффициенты корреляции Пирсона и уровни канцерогенного риска. Результаты. Содержание бензола, бензина, этилбензола и этенилбензола в отдельные периоды времени превышало предельно допустимую концентрацию в 5 и более раз; формальдегида, бенз(а)пирена и углерода (сажи) – в 2 раза. Уровень впервые выявленной онкологической заболеваемости за 2007–2017 гг. повысился на 6,0 %, уровень контингента онкобольных – на 6,9 %. Смертность от онкологических заболеваний за последние 4 года достигла максимума за весь рассматриваемый период – 200,1 на 100 тыс. населения (средний показатель за 2007–2017 гг. – 165,6±15,6). Выявлена тесная корреляционная связь между контингентом больных злокачественными новообразованиями и выбросами углерода (r=0,74), этилбензола (r=0,63). Содержание трихлорметана тесно коррелирует с показателями первичной онкологической заболеваемости (r=0,82) и смертности от онкологии (r=0,78). Уровень суммарного канцерогенного риска, обусловленного загрязнением атмосферного воздуха, составляет 9,0×10-4, что классифицируется как неприемлемый. Уровень популяционного аэрогенного канцерогенного риска составляет 1000 дополнительных (к фоновому) случаев злокачественных новообразований. Выводы. При сохранении существующих уровней загрязнения атмосферного воздуха г. Уфы возможно дальнейшее обострение экологических проблем, связанных с канцерогенными рисками, и сокращение продолжительности жизни жителей мегаполиса. Ключевые слова: загрязнение атмосферного воздуха, канцерогены, онкологическая заболеваемость и смертность, риски здоровью населения.

scholarly journals Public Health Risk Assessment Due to Air Pollution in the Temir District of the Aktobe Region

2020 ◽  
Vol 8 (E) ◽  
pp. 481-487
Author(s):  
Laura Sakebayeva ◽  
Valentina Sabyrakhmetova ◽  
Gulsim Karashova ◽  
Perizat Aitmaganbet ◽  
Kulyan Shayakhmetova
Keyword(s):  
Public Health ◽  
Risk Assessment ◽  
Air Pollution ◽  
Risk Analysis ◽  
Health Risk ◽  
Health Risk Assessment ◽  
Carcinogenic Risk ◽  
Malignant Neoplasms ◽  
Female Population ◽  
Public Health Risk

BACKGROUND: This article focuses on the health risk assessment associated with air pollution for the population of the Temir district in the Aktobe region. The risk assessment of the effects of air pollution on public health revealed a tendency to deterioration in the health indicators of the children’s population. AIM: The research object was the population of the Temir district living near the oil and gas field Zhanazhol. METHODS: The work was carried out according to the risk assessment methodology described in the manual R 2.1.10-1920-04. The maximum non-carcinogenic risk due to exposure to chemicals in the air basin of residential areas was established for children from 0 to 6 years of age in the Temir district. RESULTS: A high risk of respiratory, blood, and cardiovascular diseases was observed. Sulfur dioxide, hydrogen sulfide, nitrogen, and carbon oxides contained in atmospheric air contribute to the risk of developing these diseases. The levels of carcinogenic risk to public health in the Temir district show that the maximum individual risk of oncological diseases is observed in the group of children. The risk of malignant neoplasms in adolescents is 1.2 times lower, in the male population – 1.4 times lower, on average, and in the female population – 1.3 times lower than in children. Public health risk analysis aims to select the best ways in a particular situation to eliminate or reduce risk associated with air pollution for the population. CONCLUSION: The methodology of a comprehensive health risk analysis is a promising and developing approach in the system of monitoring the quality of the human environment and assessing environmental hazards.

scholarly journals HYGIENIC ASSESSMENT OF AMBIENT AIR AND NON-CARCINOGENIC RISK FOR PUBLIC HEALTH LIVING ON BORDER TERRITORIES

2019 ◽  
pp. 29-35
Author(s):  
V.M. Boev ◽  
E.A. Kryazheva ◽  
L.Kh. Kudusova ◽  
D.A. Kryazhev ◽  
S.V. Perepelkin
Keyword(s):  
Public Health ◽  
Air Pollution ◽  
Atmospheric Pollution ◽  
Ambient Air ◽  
Carcinogenic Risk ◽  
Ambient Air Pollution ◽  
Oil Refining ◽  
Malignant Neoplasms ◽  
Qualitative Composition ◽  
Orenburg Region

The purpose of the research study was the identification and quantitative assessment of ambient air pollution with risk assessment to public health on the territories of the Orenburg region, bordering the Republic of Kazakhstan. A hygienic assessment of thirteen border municipalities of the Orenburg region was carried out in the paper. We conducted an ambient air analysis for 23 substances, which are under long-term dynamic observation and a non-carcinogenic risk to public health was calculated. It was established that the Western and Central parts of the border territories differing in the qualitative composition of pollutants have the highest level of anthropogenic air pollution. At the same time, the qualitative composition of pollutants in the Western part of the border territory is mainly represented by substances that originate from gas and oil refining facilities. Priority pollutants in the Central part of the border territory are substances that originate from non-ferrous and ferrous metallurgy facilities. Climatic data analysis in the study territory has shown that conditions for the transboundary transfer of atmospheric pollution, both from Kazakhstan and from the Russian Federation can be created with certain meteorological parameters. Non-carcinogenic health risk analysis showed the probability of adverse effects development on organs and systems, as well as the probability of malignant neoplasms occurrence in the population living on the border territories. The study justifies and confirms the need to develop a system for monitoring and to assess the probability for transboundary transport of atmospheric pollution, as well as practical recommendations and preventive measures to reduce anthropogenic load.

scholarly journals СERVICAL CANCER’S EPIDEMIOLOGY IN THE REPUBLIC OF KAZAKHSTAN AND IN THE WORLD. IMPACT OF POPULATION ADHERENCE ON COVERAGE AND SUCCESS OF CERVICAL CANCER SCREENING PROGRAMS

2021 ◽  
pp. 26-31
Author(s):  
I.A. Zhetpisbayeva ◽  
Sh.K. Sarmuldayeva ◽  
N.E. Glushkova ◽  
E.A. Fedyanina
Keyword(s):  
Public Health ◽  
Cervical Cancer ◽  
Cancer Screening ◽  
Cervical Cancer Screening ◽  
Age Groups ◽  
Malignant Neoplasms ◽  
Female Reproductive System ◽  
Screening Programs ◽  
The World ◽  
The Republic

For many years, the problem of the prevalence of cervical cancer has been one of the most pressing for public health in most countries of the world. Despite the increasing number of screening programs, cervical cancer is still one of the most common sites of malignant neoplasms of the female reproductive system. Screening programs are effective if they involve 70% or more of the population in the appropriate age groups. In Kazakhstan, this figure for cervical cancer screening is 48–50%. [1,2,3]

A Study on Knowledge, Attitude, Awareness and Practice About HIV/AIDS among different age group of Karachi, Pakistan

2017 ◽  
Vol 3 (3) ◽  
pp. 328-333
Author(s):  
Safia Mehmood ◽  
Sheema Zia ◽  
Nida Aziz ◽  
Omama Sajid
Keyword(s):  
Hiv Transmission ◽  
Age Groups ◽  
World Population ◽  
Major Barrier ◽  
Initial Stage ◽  
Awareness Programs ◽  
And Gender ◽  
Strongly Agree ◽  
High Level ◽  
Lack Of Knowledge

The AIDS is one of the most complicated health problems of the 21st century and it threatens the world population. AIDS spread at an alarming rate. This was a descriptive study to determine the knowledge, awareness, and practice about HIV among different age groups. The study carried out in Karachi, Pakistan during the period of January 2016-april 2016, in which 82 peoples are participated; 65 peoples having age in between 18-30, people’s lies in 31-40 years, while only 4 peoples having age above 40. From which 91% peoples thought HIV is dangerous virus and 51% peoples having misconception that it cause AIDS on initial stage and does not have any effect on CD4+. Majority of peoples aware about transmission of AIDS through intercourse, and during pregnancy. But the study show the high level of misbelieve also in mode of transmission that HIV transmit through sweat, saliva etc. Majority of the peoples have knowledge that HIV-1 is the most common type found worldwide. Also large number of peoples have knowledge that HIV weak immune system by destroying CD4+ and require long exposure to progress AIDS. Less than 15% of peoples strongly agree that AIDS is common in women. This misconception reflex the lack of knowledge and awareness in the HIV transmission and gender relation. Also majority of peoples thought that lack of knowledge is major barrier in the proper cure of disease. So increasing knowledge by awareness programs; sexual prevention; by starting national testing resources and curing poverty will cured AIDS in Pakistan. Newly drugs are introduced which can stop the progression of AIDS.

Developmental Disorders in Canada

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Sarah Palmeter
Keyword(s):  
Public Health ◽  
Developmental Disorders ◽  
Health Agency ◽  
The Public ◽  
Age Of Diagnosis ◽  
High Level ◽  
Project Objectives ◽  
Disability Severity ◽  
Occupational Function ◽  
Improve Health

In the completion of my practicum at the Public Health Agency of Canada (PHAC) this summer, I worked to develop a surveillance knowledge product to support the national surveillance of developmental disorders. This project used Statistics Canada’s 2017 Canadian Survey on Disability to investigate the burden of developmental disorders in Canada. Developmental disorders are conditions with onset in the developmental period. They are associated with developmental deficits and impairments of personal, social, academic, and occupational function. The project objectives are to estimate the prevalence of developmental disorders in Canadians 15 years of age or older, overall and by age and sex, as well as report on the age of diagnosis, disability severity, and disability co-occurrence in those with developmental disorders. The majority of the analysis has been completed and preliminary results completed, which cannot be released prior to PHAC publication. Although not highly prevalent, developmental disorders are associated with a high level of disability in young Canadians. Early detection and interventions have been shown to improve health and social outcomes among affected individuals. Understanding the burden of developmental disorders in Canada is essential to the development of public health policies and services.

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