Preconditions

1. Magento version 2.1.3

Steps to reproduce

1. Go to http://www.dev.atlanticbooks.com/subjects/business-management
   OR
2. Go to http://www.dev.atlanticbooks.com/about-us

Error occuring on some of the category pages only.

Expected result

1. website should open that page

Actual result

1. Fatal error: Allowed memory size of 1388314624 bytes exhausted (tried to allocate 83 bytes) in /home/devatlanticbooks/public_html/vendor/magento/zendframework1/library/Zend/Db/Statement/Pdo.php on line 293