Dynamically pass meta_key variables into query_posts

Hi guys, this is what I want to achieve – but I have no clue how to manage to do this dynamically.

1. get the meta values of all keys of a specific metabox where the meta value is = 1
or get all the meta values of meta keys that start with “prodcat_” where the meta value is = 1 (I have no idea which is easier/works at all)
2. pass the associated meta keys into individual variables (e.g. $prodcat)
3. which can then be used to feed a custom query to define the posts listed on a page (see below)

// The Query
$args = array(
	'post_type'=> 'page',
	'post_status'=> 'publish',
	'meta_query' => array(
			//'relation' => 'OR',
			array(
				'key' => $prodcat1,
				'value' => 1
			),
			array(
				'key' => $prodcat2,
				'value' => 1
			),
			array(
				'key' => $prodcat3,
				'value' => 1
			),
			// and so on, depending on the number of results
	),
	'orderby'=> 'title',
	'order'    => 'ASC'
);
query_posts( $args );

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