: In Pakistan, marine pollution is a major problem that is caused by the waste from industrial, municipal,agronomy, and oil leak sources. The pollutant loads along with the coastline areas near Karachi is received fromterrestrial contaminants including discharges from Karachi Harbour located on the estuary of the Lyari river. Karachigenerates 472 Million Gallon per Day (MGD) of wastewater out of which only 55 MGD is treated and the rest isdischarged in the sea. The prevailing sewage treatment plants are functioning at reduced capacity due to the insufficienttransmission capacity of interceptors. Water sampling was carried out from the Lyari River and five different selectedcoastal point around Karachi harbour for physicochemical parameters and selected heavy metals. Results show that theKarachi Harbour area is noticeably polluted, whereas; the coastal environment in the vicinity of Karachi is also underthe stress of pollution. High COD and BOD5 values were noticed at the Lyari river samples and the sampling locationsclose to the Lyari river outfall area. The Pb, Cd, Ni, and Hg heavy metals that pollute marine water are found. Thissituation is due to the discharge of mixed effluents of industrial and domestic wastes as well as dredging, cargohandling, dumping of ship waste and other coastal activities. The highest value of pollution observed at KarachiHarbour which is near Lyari river mouth, where the domestic and industrial effluents with organic and inorganic wasteshave a greater influence on the water quality and the marine environment. At present, there is no effective controllingmechanism for industries to treat their waste, nor has any investigation to assess increasing marine pollution beencarried out. As a result, there is an adverse impact on fish habitat and mangroves, corrosion of cargo ships, navalvessels and the residents living in the coastal area. Therefore, the government agencies and industrial sectors shouldwork together to avert marine pollution and attain total environmental sustainability.

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Air quality in Karachi, Pakistan appears to be deteriorating in the world due to rapid increase in population, economic growth and subsequent increase in urbanization and energy demand. This study Re-is about the cumulative effects of anthropogenic activities on air chemistry of the study area atmosphere with ground base concentration measurements of gaseous air pollutants (SO2, NO2, CO, CO2 and O3), particulates (PM10 and TSP), Methane, Lead and Noise with temperature and seasonal influences on Karachi city. The primary goal of this study was to define spatial and temporal distribution of air pollutants with ArcGIS, seasonal behavior of airborne contaminants, convert the five major pollutants termed as criteria pollutants into Air Quality Index (AQI) and their temperature association for future prospects. The maximum average values of four seasons concentrations of air pollutants were found SO2=64.5 ug/m3 (GR), NO2=55.5 ug/m3 (FB), CO= 8.00 mg/m3 (CC), CO2=645 ug/m3 (NZ), O3=56.7 ug/m3 (ST), PM10=225 μg/m3 (CC), TSP=402 ug/m3 (CC), Methane=1.65 m/gm3 (CC), Lead=5.1 ug/m3 (ST), and Noise=85 dB (GR). The minimum four seasons average concentration values with monitoring location as {SO2=48.2 ug/m3 (FB), NO2=44.6 ug/m3 (NZ), CO=4.1 mg/m3 (BC), CO2=601 ug/m3 (JH), O3=42.4 ug/m3 (GR), PM10=150 ug/m3 (BC), TSP=226 ug/m3 (JH), Methane=0.68 mg/m3 (BC), Lead=32 ug/m3 (GZ), and Noise=81 dB (BC). The spatial-temporal analysis of air quality revealed that the pollutants in the summer are higher in industrial and high-density traffic junctions. In this study, temperature and air quality are significantly associated, while rainfall and relatively high humidity days are negatively correlated. High temperature months have highest air pollution values, whereas the washout impact of precipitation and relative humidity have the lowest levels. The analysis of air quality index parameters demonstrated a high coherence among NO2, CO and O3 with variation in

Pakistan’s urban air pollution is amongst the utmost severity in the world that causes acute damage to the economy and human health. This study was designed for the assessment of ambient air quality in different areas of Karachi. The data were collected as pre-monsoon and post-monsoon season from main industrial zones of Karachi, S.I.T.E area, North Karachi industrial area, Korangi industrial area and Landhi industrial area in the year of 2017-2019. These zones are also a blend of industrial, residential, commercial and heavy traffic zones with dense populations. Ambient air data were collected for different pollutants like Nitrogen Oxides (NOx), Carbon Monoxide (CO), Sulfur Dioxide (SO2) and Particulate Matters (TSPM, PM10 and PM2.5). It is observed that in pre-monsoon, there is quite high intensity of particulate matter (TSPM, PM10 & PM2.5) present in the air, whereas CO and NO2 values found in all four zones are moderate in the air samples as prescribed by Sindh Environmental Protection Agency (SEPA) standards. It is observed specifically in Landhi, S.I.T.E Area and Korangi industrial area which are more prone to the exposure of these pollutants. In post-monsoon, the intensity of particulate matters (TSPM, PM10 & PM2.5), CO and NO2 values in all four zones are less to moderate than the values of pre-monsoon due to the seasonal effects. Study data shows that three major zones; Landhi, Korangi and S.I.T.E. industrial areas are at a high exposure to gases and other toxic elements. North Karachi is at the least risk because of having a small scale of industries present. The PM10 & PM2.5 levels average about 2 - 3-fold greater than the SEPA standards. High levels of ambient air pollutants cause severe health problems and chronic diseases on human health. Therefore the implementation of rules and regulations regarding ambient air pollutants should be more rigorous.

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