| Re-assessment of the titration method for determination of organic carbon in recent sediments OA El Rayis Rapp Comm Int Mer Medit 29 (7), 1985 | 123 | 1985 |
| Re-assessment of chelating ion-exchange resins for trace metal analysis of sea water MI Abdullah, OA El-Rayis, JP Riley Analytica chimica acta 84 (2), 363-368, 1976 | 79 | 1976 |
| Zinc oxide nanoparticle toxicity in embryonic zebrafish: Mitigation with different natural organic matter SM Kteeba, HI El-Adawi, OA El-Rayis, AE El-Ghobashy, JL Schuld, ... Environmental pollution 230, 1125-1140, 2017 | 68 | 2017 |
| Occurrence and distribution of chemical pollutants in Lake Mariut, Egypt. II. Heavy metals MAH Saad, AA Ezzat, OA El-Rayis, H Hafez Water, Air, and Soil Pollution 16, 401-407, 1981 | 60 | 1981 |
| Status of nutrients in Lake Mariut, a delta lake in Egypt suffering from intensive pollution MAH Saad, OA El-Rayis, HH Ahdy Marine Pollution Bulletin 15 (11), 408-411, 1984 | 41 | 1984 |
| Impact of man’s activities on a closed fishing-lake, Lake Maryout in Egypt, as a case study O El-Rayis Mitigation and Adaptation Strategies for Global Change 10, 145-157, 2005 | 39 | 2005 |
| Environmental conditions of two Red Sea coastal lagoons in Jeddah: 1. Hydrochemistry OA El-Rayis, MO Moammar Journal King Abdulaziz University Earth Science 9, 31-47, 1998 | 33 | 1998 |
| Exposure to ZnO nanoparticles alters neuronal and vascular development in zebrafish: Acute and transgenerational effects mitigated with dissolved organic matter SM Kteeba, AE El-Ghobashy, HI El-Adawi, OA El-Rayis, VS Sreevidya, ... Environmental pollution 242, 433-448, 2018 | 31 | 2018 |
| Preliminary investigations of some heavy metals in water, sediments and plankton in odhur creek (eastern red sea) AKAB BEHAIRY, OAELR EL-RAYIS, AMI IBRAHIM Marine Scienes-Ceased lssuerg 17 (3), 1-2, 1986 | 26 | 1986 |
| Environmental conditions of two Red Sea coastal lagoons in Jeddah. 2-Nutrients OA El-Rayis JKAU: Mar. Sci 9, 49-59, 1998 | 22 | 1998 |
| Occurrence of some trace metals in bottom deposits from Abu Kir Bay, Egypt MAH Saad, OA El-Rayis, FE El-Nady Journées Etud. Polut. CIESM 6, 555-560, 1980 | 21 | 1980 |
| Levels of trace metals in some food chain organisms from El-Mex Bay, west of Alexandria, Egypt OA El-Rayis, O Abouldahab, Y Halim, JP Riley Proceedings of the 7th international conference: environment protection is a …, 1997 | 20 | 1997 |
| Concentration of Cu, Cd, Zn, Fe and Mn in the Nile river water and its contribution to the Mediterranean AO El-Rayis, MAH Saad Rapports et procès verbaux des réunions-Commission internationale pour l …, 1985 | 20 | 1985 |
| Water quality assessment and phosphorus budget of a lake (Mariut, Egypt) after diversion of wastewaters effluents MA Shreadah, OA El-Rayis, NA Shaaban, AM Hamdan Environmental Science and Pollution Research 27, 26786-26799, 2020 | 19 | 2020 |
| Contribution of some trace elements from an Egyptian huge drain to the Mediterranean Sea, West of Alexandria OA El-Rayis, MA Abdallah Egyptian Journal of Aquatic Research 31, 120-129, 2005 | 19 | 2005 |
| Distribution of some heavy metals in sediments, water and different trophic levels from Jeddah coast, REDSEA. JKAU OA El-Rayis Mar. sci 3, 33-45, 1989 | 18 | 1989 |
| Occurrence of organic matter and heavy metals in sediments from the Mediterranean MAH Saad, OA El-Rayis, FE El-Nady Management of Industrial Wastewater in Developing Nations, 127-139, 1981 | 17 | 1981 |
| Some hydrochemical observation from Lake Mariut prior to diversion of sewage of eastern districts of Alexandria OA El-Rayis, MA El-Sabrouti, HM Hanafy Proc. 1st. Arab. Conf. Mar. Environ. Protec.(AMTA), 205-219, 1994 | 16 | 1994 |
| Contribution of nutrients and some trace metals from a huge Egyptian drain to the SE-Mediterranean Sea, west of Alexandria OA El-Rayis, MAM Abdallah Mediterranean Marine Science 7 (1), 79-86, 2006 | 15 | 2006 |
| Heavy metal pollution in lagoon Mariut on the southern coast of the eastern Mediterranean Sea OA El-Rayis, MAH Saad JKAU Sci 1, 17-26, 1990 | 15 | 1990 |
